I'd like to put all manufacturers of double-ended dildos on notice that you are failing in your product descriptions on your websites.
Specifically - here's where you are blowing it...
Your products are designed for a woman to insert one end of the toy inside herself and use the other end of the toy in her partner. Awesome so far. But you seem to have forgotten one important fact.
Her partner can be either male or female.
Now, who knows what the gender percentages are; I don't believe those studies have been done yet. But to direct your advertising towards only one segment of that group is...blowing it.
How, specifically, are you blowing it?
You are making the claim on your manufacturer's websites that your product is designed to be used without a harness without differentiating between heterosexual or lesbian use.
It could be that you don't read the forum boards or you don't have any heterosexual customers testing your products. Perhaps you just are too attached to the "strapless" claim. Maybe your product was really designed for lesbian strap-on sex and you just don't care that there are hetero couples out there that might add to your sales. Or maybe you just want the initial sale and since you don't sell harnesses you don't really care what happens after that. I would like to believe you care more about your customers than that. After all, we are talking profits here.
You see... there are a LOT of heterosexual couples who try to use your products without a harness, fail and then seek advice.
In my estimation approximately 95% of women who are engaging in heterosexual strap-on sex - also called "pegging" - must use a harness to keep your product inside them. Why? Because anal sphincter muscles are stronger than vaginal muscles, no matter how many Kegels a woman does. Very, very few women are able to use a double-ended dildo for pegging without a harness. And yet you advertise it that way.
So couples try it, get frustrated and discover they need a harness. Sometimes these couples even give up and pegging is taken off the table completely - most often by the women - who experience most of said frustration. Sometimes these women even end up feeling "less than" because they are told that if their muscles were strong enough they could keep the toy inside them.
By the time they purchase a harness and get it right (if they indeed push past the frustration), their enthusiasm for recommending your product has lessened considerably from when they first bought it. And they may even have a touch of resentment that the advertising of your product did not mention a harness is usually essential to successful use, which alienates customers from additional purchases.
What you want is success stories with your product. Success stories boosts sales.
Fuze Tango says, "works perfectly with a harness".
Not bad. But it would be better to say a harness is recommended for pegging.
Tantus' Feeldoe/Realdoe has "patented strapless strap-on" claims all over the website. The only mention of a harness is very hard to find and says, "If you just love your leathers, or haven't done your Kegel's don't fret, an old fashioned 3 strap harness will fit it! Bike shorts work wonders, too, and fittingly so since it really is like learning to ride a bike."
Cute, but implies that most women should be able to use it without a harness. And they even say that 80% of their sales are to heterosexual couples! You'd think they would give them more accurate information since that is the bulk of their sales.
Fun Factory Share says, "without a harness", "suitable for harnesses", and "...slight ridge for improved hold..." depending on whether you are looking at the Share XL, the Share or the Share XS (in that order).
Confusing and inaccurate.
The less well-known doubles don't do any better...
Eternal Swan (not in USA) says, "created to be worn without a harness".
Ummm...for whom? Not for heterosexuals.
Fetish Fantasy Elite 8" Strapless Strap-On says, "hands-free penetration without a harness or strap" and claims, "It's great to use on both sexes".
Misleading and inaccurate.
I remain puzzled by the lack of factual information for heterosexual couples exploring strap-on equipment. The couples are often new at this, so they need good information. They are also the majority of your sales - so it would behoove you to pay attention and give them what they need to make a good purchasing decision.
Thankfully, some retailers are putting more information on their websites through reviews as well as product descriptions. Hopefully the manufacturers will realize the importance of informing their customers with facts and recognizing the large share of the double dildo market that heterosexuals comprise.
Update - A more in-depth article here: The Truth About Strapless Strap-ons