Fetish Fantasy Beginner's Hollow Strap-On: review

Fetish Fantasy Beginner's Hollow Strap-On in brief

Fetish Fantasy Beginner's Hollow Strap-On is a hollow strap-on in PVC with an adjustable elastic harness. It is manufactured by Pipedream Products and is part of the brand’s Fetish Fantasy Series. The specification is short enough to fit in one sentence: insertable length 15 centimeters, diameter 4.5 centimeters, a hollow chamber 10 centimeters deep and 3.5 centimeters in diameter, and a strap made of elastic fabric. No batteries, no motor, no settings, and nothing to charge.

Being hollow is the whole point. A regular strap-on replaces a penis. Instead, this one can be threaded over one, which means the same item covers three completely different uses: as support when an erection isn’t enough, as a size-enhancer, and as a regular strap-on when the wearer doesn’t have a penis to put into it. That’s why the manufacturer itself named the item For Him or Her Hollow Strap-On.

In Sweden, the item is sold by five stores at prices between 299 and 469 SEK, and four of them had it in stock at the price check on September 12, 2026. This review is exclusively about the light variant with EAN 603912160352, the manufacturer’s item number PD3366-21. The same model is also available in black (EAN 603912160369) and in purple (EAN 603912160345) at the same list price, and those numbers therefore aren’t interchangeable when you compare prices.

What does a hollow strap-on do that a regular one doesn’t?

The difference is structural and easy to describe. A solid dildo is solid all the way through. A hollow dildo has a chamber in the base that goes a bit up into the shaft. The manufacturer specifies that chamber as 10 centimeters in length and 3.5 centimeters in diameter. In practice, that means a penis—fully or partially erect—can be placed inside the dildo, and that the dildo then functions as an outer shell.

Three consequences follow from that. The first is that the product works even when an erection is missing or goes away, because it’s the PVC shell—not the penis—that supports the shape. The second is that it adds extra girth: the outer measurement is 4.5 centimeters in diameter versus 3.5 centimeters for the chamber, which means the shell adds about one centimeter all around in width. The third is that it can be worn by anyone, with or without a penis, because the harness keeps the dildo up regardless.

What can be stated purely technically is that the chamber’s dimensions set the limit for who the construction works for. A 10-centimeter inner length is somewhat shorter than the average for an erect penis, which means that in normal use the wearer doesn’t fit all the way in—the outermost part of the shaft fills the chamber and the rest remains at the base. That’s a trade-off the manufacturer has made intentionally: a deeper chamber would have required a longer dildo, and 15 centimeters is exactly the measure that makes the model a beginner product rather than an extreme model.

Beginner's, For Him or Her, or Hollow Harness — why the name changes

This item is sold in Sweden under five different names, and it’s worth knowing before you start comparing. The manufacturer’s own name is For Him or Her Hollow Strap-On. Vuxen calls it Beginner's Hollow Strap-On, Sexonic Fetish Fantasy Series Flesh Adjustable Hollow Harness 15 Cm, Lekosmek Hollow Strap on – 15 cm, Taboo Ihålig Strapon 15 cm and Mshop Fetish Fantasy Hollow Strap-On 15 cm Light.

The name "Beginner's" likely comes from the packaging. The product image Vuxen publishes shows a cardboard box with the headline "Perfect For Beginners!" across the top, plus a round decal marked "Free mask inside". The manufacturer’s current packaging image lacks both the headline and the decal and only lists two things in the box labeled "Includes": a 6-inch (15 cm) dildo and an elastic harness. So don’t assume that an eye mask is included—the manufacturer’s current packing contents do not include it, and none of the five shops list it either in their contents list.

The only thing that ties the five shop names together is the EAN number. All five list the item under 603912160352, either directly in their structured product data or under the manufacturer’s item number PD3366-21. Check that number, not the name, when you compare price.

Dimensions: 15 centimeters insertable and 4.5 centimeters in diameter

The manufacturer publishes exactly four measurements for this item, and they are all given in both inches and centimeters: insertable length 6 inches / 15 centimeters, width 1.75 inches / 4.5 centimeters, inner length 4 inches / 10 centimeters and inner diameter 1.5 inches / 3.5 centimeters. That’s the entire measurement list. Everything else you find at the shops is the shops’ own information, and it varies.

Inner measurements 10 × 3.5 centimeters — who is it for?

The inner diameter is the number that determines whether the product works for the wearer. 3.5 centimeters in diameter corresponds to a circumference of a little over eleven centimeters, which is below average for an erect penis. It isn’t a design flaw but a requirement: the material is softened PVC and stretches, and a chamber that would already be spacious from the start wouldn’t stay in place.

At the same time, it’s the most common reason why a hollow strap-on doesn’t work the way the buyer intended. If you’re on the upper end of the size range, it’s the chamber’s diameter, not the dildo’s outer dimensions, that becomes the limiting factor. Feel free to compare with the manufacturer’s larger sister model: Fetish Fantasy Series 9" Hollow Strap-On with Balls has an inner diameter of 4.5 centimeters, which is one full centimeter more, for an inner length of 9.9 centimeters. If you want the same length but more space inside, then there’s an alternative within the same series.

For the one who will wear the product without their own penis, the internal measurements don't matter at all. Then the chamber is just an empty space, and the only thing you notice about it is that the base becomes a bit wider and softer than on a massive dildo with the same outer dimensions.

Total length and weight: what the manufacturer doesn't publish

Pipedream does not publish total length, weight, or waist measurements for this product. It’s a notable gap, because the manufacturer publishes all three for the sister model with balls — there, total length is given as 24 centimeters and waist measurement is 71.1 to 132.1 centimeters. The information is thus in the manufacturer’s format; it has simply not been filled in for this article.

The shops fill in the gap on their own, and this is where the details start to differ. The retailer Vuxen lists the total length as 19.5 centimeters, which is 4.5 centimeters more than the insertable length — reasonable, since the base flange and the chamber opening sit outside the insertable measure. The retailer Taboo states a weight of 335 grams in its structured product data, and Lekosmek states the same weight in its. That two shops independently provide the same figure makes the number more likely than a single claim, but it’s still a shop’s specification and not a manufacturer’s one.

A counterexample shows why this distinction matters. The retailer Sexonic lists the weight as 1,000000 kilogram in its product data. It’s clearly a shipping template rather than a weighing of the product, and the difference compared to 335 grams is almost three times. A weight figure in a shop listing is often a shipping weight, and it should be read as such until the manufacturer says something else.

Harness: elastic one-size without a published waist measurement

The manufacturer describes the harness as an adjustable elastic harness and states the material as elastic fabric, but does not publish any waist interval. The retailer Mshop states that the harness fits a circumference from 66 to 120 centimeters. The retailer Taboo describes it as one-size with adjustable elastic straps without giving any measurement, and Mshop also calls the harness "nylon", while the manufacturer only writes "elastic". Where the manufacturer and the shop say different things, the manufacturer’s statement applies — so what can be established is this: elastic fabric, adjustable, waist measurement not published.

The comparison with the sister model is still informative. The manufacturer lists 71.1 to 132.1 centimeters for the 9-inch model’s harness. So Mshop’s range of 66 to 120 centimeters is narrower at both ends, which makes sense for a smaller product but is still a shop specification. If you’re at the outer edges of that range — below 66 or above 120 centimeters in waist circumference — it’s worth measuring before you order, since neither of the figures comes from the manufacturer.

The construction is of the simplest kind in the category: elastic bands with metal snap buttons that keep the dildo’s base in place. That means there are few parts that can break, but it also provides less stability than a harness with buckles and a rigid plate. The manufacturer explicitly uses “heavy-duty metal hardware” as a selling point on the larger sister model but not on this one, which is worth noting considering the price difference is still small.

Material: PVC and elastic fabric

The manufacturer’s material declaration for this item consists of two words: PVC and elastic. PVC stands for dildo, and elastic stands for harness. That’s the entire declaration—no breakdown by part beyond that, no information about which softeners are included, and no stated guarantee about phthalates.

What PVC means for hygiene and service life

PVC is not the same type of material as silicone, and the difference is crucial in this product category. Silicone is non-porous: the surface has no microscopic voids, which makes it possible to clean it thoroughly. Plasticized PVC is porous in practice, and a porous surface can be washed but not sterilized. Residues and bacteria can remain in the surface layer, and the surface also breaks down slowly as the softeners migrate out of the material.

What can be established is that it gives the product a shorter hygienic service life than a silicone product. A PVC dildo that has become sticky, discolored, or developed a changed odor should be replaced, not rescued—it's the softener that has left the material and the surface that has started to break down. The manufacturer states no expected service life, and none of the five stores does either.

The practical conclusion is that putting a condom over the dildo is a reasonable routine with this product, and next to necessary if it’s going to be shared between partners or switched between anal and vaginal use. It’s also the simplest way to extend the material’s service life, because the contact surface is then protected from both bodily fluids and lubricants.

Phthalate question: the stores claim it, the manufacturer stays silent

Here there is a clear conflict in the sources, and it deserves to be presented plainly. Pipedream publishes no phthalate declaration for this item—neither on the product page, in the material field, nor in the product description. Two Swedish stores do it instead on their own: Vuxen writes “body-safe and free from phthalates” in its specification table, and Mshop lists “phthalate-free, latex-free, body-safe” among its highlights. None of them states where the information comes from.

Why the question matters for PVC specifically is shown in the Swedish Chemicals Agency’s (Kemikalieinspektionen) desk review of the information. Phthalates are used primarily as plasticizers in polyvinyl chloride, and as plasticizers they can make up up to half of the material. They are added via external plasticizing, which means they are not chemically bound to the plastic but can relatively easily leak out—and they can keep leaking out as long as the material is being used. Several low-molecular-weight phthalates are classified as reproductive toxicants and identified as endocrine disruptors.

At the same time, there is a legal bottom line. In the EU, DEHP, DBP, BBP and DIBP may not be present in concentrations above 0.1 weight percent in plasticized material in products, and the rules were tightened further in 2024. So a product that is legally sold in Sweden must meet that limit for the four substances. What does not follow from that is that the material is free of all phthalates or of other plasticizers—only that the four regulated ones are below the limit.

The conclusion is therefore twofold. The retailers’ claims are reasonable but unsubstantiated, and the manufacturer’s silence is the only information we can state. If you want an explicit material declaration from the manufacturer, it isn’t provided in this article—then the silicone alternative further down in the text is what actually delivers it.

Which lubricant works with PVC?

The manufacturer publishes no lubricant recommendation for this specific article. On the larger sister model in the same series, though, Pipedream expressly states that the dildo is compatible with both water-based and silicone-based lubricants, and that it’s cleaned with an antibacterial cleaning agent and warm water. The retailer Mshop recommends a water-based lubricant for this article.

So the practical advice is a water-based lubricant. It’s the variant that’s safe against all materials in the category, it’s easy to rinse off, and it’s the only recommendation that’s actually published for this article. Oil-based products like coconut oil leave a film that’s difficult to remove from a hollow chamber, and they also break down latex if you use a condom over the dildo.

Use: three situations the product is built for

The manufacturer’s own product text names three uses, and those three explain why the article exists: woman-to-woman, anal use where the recipient is a man, and as support for the person who has difficulty getting or keeping an erection. That’s unusually concrete for a product text in this category, and it makes it easier to determine whether the product actually solves the problem you’re buying it for.

Support for erectile problems

This is the use that the hollow construction is most specifically designed for. Since the shell supports its own shape, the function is independent of how much erection the wearer has. The harness holds the dildo in place against the body, and the chamber measuring 10 by 3.5 centimeters receives whatever is there.

What can be established is that the construction is mechanical, not medical. It solves a practical problem—penetration doesn’t work—but it treats nothing. Erection problems often have an underlying cause that’s worth discussing with healthcare, and a strap-on is a tool alongside that, not a substitute for it. The manufacturer makes no medical claims about the product, and it shouldn’t either.

A practical detail that follows from the measurements: since the chamber is shallower than the dildo, there will be a section of casing in front of the wearer that is completely hollow. That part has no sensation at all, which is the whole point of the construction but also its limitation—the wearer gets less direct stimulation than during unprotected intercourse.

For pegging and woman-to-woman

Worn without a penis inside, the product works like a standard strap-on. A 15-centimeter insertable length and a 4.5-centimeter diameter are sensible dimensions in this context, which is appropriate for an article marketed to beginners. For comparison, the manufacturer’s 9-inch model has a 22.9-centimeter insertable length—almost eight centimeters more—and the 8-inch model in the same series comes in between.

For anal use, there’s a construction detail worth mentioning: the dildo lacks testicle balls and instead has a relatively narrow base that transitions into the chamber opening. This makes the product easier to aim than a model with balls, but it also means the base is less wide. The manufacturer does not publish a base measurement separately. For anal use with a strap-on, the dildo is secured in the harness, which in itself solves the safety issue of loose anal toys.

Plenty of lube is not a tip but a requirement for anal use, and PVC as a material creates less friction when it’s wet than when it’s dry. Plan on topping up along the way—water-based lube dries out faster than silicone-based.

How to make the harness sit

The harness is made of elastic fabric with metal snap buttons. Adjust it before the dildo is in place, not after—an elastic band that’s already been loaded is harder to get evenly. Two bands go around the hips, and one goes between the legs, and it’s that last one that determines how much the dildo points upward or sticks out straight.

Elastic fabric has a property that’s worth planning for: it stretches more the longer it’s under load. That means a harness that fits perfectly at the start can end up sitting looser after a while, and that’s the most common reason a strap-on in this price range starts to slip. Tighten it a bit more than you think is needed from the beginning.

Underwear under the harness straps does two things: it reduces friction against the skin and it gives the harness something to grip. It’s a common approach with elastic harness straps, and it costs nothing to try.

Cleaning, drying, and storage

The hollow design makes cleaning the most important routine for this product. A chamber that is 10 centimeters deep and 3.5 centimeters in diameter is exactly the kind of geometry where water and residue will stay put, and PVC is exactly the kind of material where that has consequences.

How do you clean a hollow strap-on inside?

Rinse the chamber with lukewarm water and fragrance-free soap or a cleaning agent intended for intimate products. Turn the product so that the opening points downward and let the water run through—since the chamber has only one opening, the liquid has to come out the same way it went in. The manufacturer states for the sister model in the same series that cleaning is done with an antibacterial cleaning agent and warm water.

Drying is the step that’s most often skipped and the one that matters the most. Leave the product standing with the opening down until the inside is completely dry before putting it away. A damp, enclosed chamber in softened plastic is a favorable environment for microorganisms, and it’s hard to see inside to check it. The routine of putting a condom over the dildo doesn’t apply to the inside—the chamber must be cleaned no matter what.

The harness straps are textile and can be hand-washed in lukewarm water. Let it air-dry; the metal parts don’t tolerate a tumble dryer, and elastic fabric loses its spring from heat.

Storage: why PVC shouldn’t be kept against other soft plastics

The plasticizers in PVC aren’t chemically bonded to the plastic, so they can leak out of the material—and that’s exactly the property that makes two soft-plastic products that are stored against each other start sticking to each other and becoming tacky. Store the product separately—preferably in a fabric bag—and not in a plastic bag or pressed against other soft-plastic sex toys. No storage bag is included according to the manufacturer’s delivery contents.

Dry, cool, and dark is the right storage. Heat speeds up the plasticizers migrating out, and direct sunlight breaks down the material. That’s also why the product shouldn’t be boiled or run through a dishwasher—PVC deforms from heat, and the manufacturer provides nothing indicating that the material would tolerate it.

Waterproofness and bath: what can be said

The question of waterproofness is often asked in this category, but it means something different for a product without electronics. The manufacturer does not publish an IP rating for this article, and that follows logically: IP ratings according to IEC 60529 describe the enclosure of electrical equipment, and this product contains no electrical equipment at all.

What can be established is that the dildo is made of plastic and the harness is made of textile with metal fittings. The dildo can withstand water in the sense that it can’t short-circuit, but the hollow chamber fills with water if the product is lowered into water, and that water has to drain out and dry before it’s put away. The harness and its metal snap buttons do better when kept dry: the textile takes a long time to dry, and metal in damp textile is a corrosion risk.

In practice, that means the product can be rinsed off but isn’t built for baths. If you want a strap-on for the shower or bathtub, it’s the harness and not the dildo that sets the limit, and that’s an argument for a model where the harness can be purchased separately.

Fetish Fantasy Beginner's Hollow Strap-On compared with the alternatives

Three comparisons are relevant, and all three fall within Pipedream’s own range: against the silicone version of the same idea, against the larger model in the same series, and against the medium-size one. All the information below comes from the manufacturer’s own product pages, and the Swedish prices from the shops’ product feeds on September 12, 2026.

Against Fantasy X-Tensions Elite 6" Hollow Silicone Strap-On

This is the comparison that matters most, because it’s the same manufacturer, the same idea, and the same length class—just a different material. Fantasy X-Tensions Elite 6" Hollow Silicone Strap-On (EAN 603912775709) is made of what Pipedream calls Elite Silicone, with a double-density construction: soft on the outside, firmer on the inside. The harness is made of nylon. The list price is $60.99 versus $45.99 for the PVC model.

The differences that actually matter are two. The material is one: silicone is non-porous and can be cleaned properly; PVC is not. The construction is the other: double density provides a firmer core in a softer surface, while the PVC model, according to Vuxens egenskapstabell, is classified as “hard” in stiffness and “lightly bendable” in elasticity.

What speaks in favor of the PVC model is the price and the fact that it’s actually available in Swedish shops with published dimensions. Pipedream does not publish any dimensions at all for the silicone model—neither insertable length, diameter, inner length, nor inner diameter, which is remarkable for a more expensive product. So you’re trading a known material for unknown dimensions—or vice versa. If hygienic service life is your most important criterion, then the silicone model is still the right way to go; if fit and price are what matters, then this one is it.

Against Fetish Fantasy Series 9" Hollow Strap-On with Balls

The sister model with ball pouch (EAN 603912362756) uses the same material and the same basic construction in a larger format. The manufacturer publishes the complete dimensions list here: total length 24 centimeters, insertable length 22.9 centimeters, width 4.6 centimeters, inner length 9.9 centimeters, inner diameter 4.5 centimeters, and a waist measurement of 71.1 to 132.1 centimeters. The list price is $65.99.

Two things stand out in the comparison. The first is that the inner diameter is a full centimeter larger—4.5 vs 3.5 centimeters—while the inner length is essentially the same, 9.9 vs 10 centimeters. So if you need more space inside, it’s the larger model that provides it, and it does so without the chamber becoming deeper.

The second is that the insertable length is almost eight centimeters longer. 22.9 centimeters isn’t a beginner model, and for the recipient it’s a completely different product. Anyone who wants the extra inner diameter but not the extra length has to look elsewhere—the combination doesn’t exist in the series. The manufacturer also highlights “heavy-duty metal hardware” and a super-stretchable harness on the 9-inch model—wording that isn’t used for this article.

Versus 8" Hollow Strap-On — same series, five centimeters longer

This comparison is especially relevant, because it’s available in the same store. Lekosmek sells both the 15-centimeter model and a variant the store calls “20 cm” on the same product page, at the same price of 369 SEK. However, the larger variant has its own EAN: 603912329889, which according to the manufacturer is Fetish Fantasy Series 8" Hollow Strap-On, item number PD3360-21, MSRP 49.99 dollars. So, this is not a size of the same item but a different item, and the 20-centimeter variant was sold out at the price check.

The manufacturer doesn’t publish any dimensions for the 8-inch model beyond the name, which makes it hard to compare in anything other than length. Practically speaking, that means that if you’re looking for a hollow strap-on with published dimensions in the Fetish Fantasy series, it’s the 15-centimeter and 9-inch models that offer that, and the middle size doesn’t.

Price range: 299 to 469 SEK at five stores

Five Swedish stores sell the item with EAN 603912160352. Cheapest is Vuxen at 299 SEK, and most expensive is Mshop at 469 SEK. That’s a difference of 170 SEK, or 57 percent, for exactly the same item number, same color, and same packaging.

The stock situation is favorable compared with most products in this category. Fyra av de fem butikerna hade varan i lager vid priskontrollen: Vuxen at 299 SEK, Lekosmek at 369 SEK, Taboo at 399 SEK, and Mshop at 469 SEK. Sexonic listed 312 SEK but it was sold out. That means the cheapest store is actually the cheapest available—something that isn’t a given: the next-cheapest store with the item in stock is 70 SEK higher.

Vuxen additionally lists a recommended price of 349 SEK and shows 299 SEK as the lowest price over the last 30 days. That means 299 is not a temporary promotional price but the store’s established level. The manufacturer’s list price is 45.99 dollars, which puts the Swedish prices in context: even the most expensive Swedish store is below the list price when converted, and that’s typical in a category where list prices are set for the U.S. retail market.

Shipping is worth keeping in mind at this price level. Mshop lists 39 SEK in shipping and free shipping over 999 SEK; Vuxen offers free shipping from 799 SEK; and Lekosmek offers free shipping over 699 SEK. On an item around 300 SEK, that means the shipping cost can make up more than a tenth of the total, and that in some cases the price order between the stores can be flipped once you add it.

When stores contradict the manufacturer

This article is a clear example of why store information should be read as exactly that: store information. The manufacturer states the diameter as 4.5 centimeters. Mshop lists 4 centimeters. Lekosmek lists 3.5 centimeters. Those are three different numbers for the same measurement on the same item number, and two of them are wrong.

The same applies to the inner diameter: the manufacturer states 3.5 centimeters, Mshop 3.4. And Lekosmek’s size description contains a direct contradiction—the store writes "Längd 15 cm (därav inre 15 cm)", which can’t be correct, since a hollow chamber can’t be as long as the entire dildo. The manufacturer states 10 centimeters.

Mshop also has an internal contradiction in its own text: the product description talks about a dildo in "black color" even though the variant sold under this EAN number is called Ljus, and even though the store’s own color selector is set to Ljus. Store text in this category is often reused between color variants without being rewritten.

Practically speaking, that means you should base everything on the manufacturer’s four measurements—15, 4.5, 10 and 3.5 centimeters—and treat everything else as estimates. This applies in particular to the diameter, which is the measurement that determines whether the product works for you.

Who is it for—and who is it not for?

It’s for you if you want to try a hollow strap-on without spending more than a couple hundred kronor on it. It’s for you if you need mechanical support for erection problems and want a solution that works regardless of the day’s condition. It’s for couples where one of the partners wants to wear it without having their own erection to build on, and it’s for the one who is looking for moderate measurements rather than maximum ones—15 centimeters insertable and 4.5 centimeters in diameter aren’t small measurements, but they’re also not extreme.

It doesn’t fit you if you set requirements for the material. PVC can’t be sterilized, and the manufacturer does not publish any phthalate declaration for this article. If you want a stated material declaration, the silicone model in the Fantasy X-Tensions Elite series is the alternative, at about one-third higher list price. It also doesn’t fit you if you’re in the upper part of the size range, because then the chamber’s 3.5-centimeter diameter becomes the limiting measure.

It doesn’t fit you if you want a harness with firmness. Elastic fabric with snap buttons is the simplest construction in the category: fewer parts, low price, but less support than a harness with buckles and a rigid plate. In addition, the manufacturer does not publish any waist measurement for this particular harness, which means that fit is the only feature you can’t control in advance against a manufacturer specification.

One more thing belongs in the decision. This article has no electronics, no battery, and no charging cable, and that’s a real advantage that’s easy to lose in comparisons with more expensive products. There is nothing that can stop it from charging, no cell that loses capacity, and no product-specific cable you can misplace. What sets the limit for lifespan is the material, and once the material is used up, 299 SEK is an affordable cost to replace it with.

Warranty, claims, and right of withdrawal

Pipedream does not publish a warranty period for this article on the product page. What exists are the stores’ own commitments, and they differ. Lekosmek states a two-year product warranty on its product page. Mshop states 100 days of open purchase. Vuxen and Taboo do not state any own warranty period on the product page.

What always applies, on the other hand, is your statutory rights—and they’re stronger than most manufacturer warranties in this category. According to konsumentköplagen, you have three years to make a complaint for defects in the goods, regardless of what the manufacturer or the store promises. For distance purchases, there is also a right of withdrawal within fourteen days according to distansavtalslagen.

A practical limitation is worth knowing in advance: in practice, the right of withdrawal is restricted for hygiene products that have been taken out of a sealed package. According to the manufacturer, this product is delivered in a cardboard box, and how the individual store handles returned opened packages determines it themselves within the law’s framework. The right to complain for defects, however, always applies—even for an opened item. If you have questions about what applies in your case, Konsumentverket guides you via Hallå konsument.

A final note on what you can actually make a claim for. On a product without electronics, there are three things that typically break: the harness’s push buttons, the seam in the elastic band, and the dildo’s material. The first two are manufacturing defects if they give way early. The third — that PVC becomes sticky and discolored over time — is normal wear of the material and not a defect within the meaning of the law, and it’s also the single most important reason to view this product as a consumable rather than a one-time investment.