SI-X Type F: The Oral Sex Masturbator

If there’s one type of sex toy many guys seem to be searching for, it’s a masturbator that replicates oral sex. There are many products out there that claim (or aim) to do just that. The SI-X Type F masturbator from Toy’s Heart is one of them.


Toy’s Heart – a company that puts out masturbation toys for the Japanese market – produces a line of masturbators that are supposed to simulate certain body parts…and the sex acts that accompany them. The SI-X Type F masturbator is supposed to offer its users the effect of a snug mouth; a guy can slide his hard cock through the tight opening and feel like he’s pumping in and out of a facsimile of a human mouth, thereby giving him an oral sex-like experience. “Type F” in this case stands for “fellatio.”

First, the basics: the SI-X Type F is a soft, squishy toy made of TPE…thermoplastic elastomer; which is mix of plastic and rubber. To squeeze it, it feels like a very firm gelatin, but it’s tough enough that it’s not going to tear too easily. I was able to turn the toy completely inside-out for cleaning (and to photograph the interior texture), and it never felt like the toy was going to tear. Since it’s a very flexible material, you can easily bend and maneuver it during use. In fact, most guys are probably going to want to squeeze and maul it to apply pressure to the textured points inside so your cock gets the most sensation out of this thing. Because it’s made of TPE, the manufacturer recommends using a water-based lube with this toy.

The SI-X has the size and shape of a regular hot dog bun, which make sense given what you’re going to put inside it. The round opening on the end is under a half inch in diameter, but the material stretches so easily that I’m guessing most guys can penetrate this without tearing it. Lengthwise, it’s six inches long; more endowed guys might want to opt for a masturbation toy with more depth, but – again – the material should easily stretch to accommodate longer guys.

The SI-X Type F is a raspberry color, inside and out. This, coupled with the perfectly round (and small) orifice makes for a less-than-realistic looking mouth, so if you’re a man who needs a visual fantasy, you’d be better off with another masturbator with more lifelike detail. The TPE material, being what it is, has somewhat of a rubbery odor to it. The scent of mine has faded a bit with repeated washings, but is still detectable. If you’re sensitive to these types of odors, or have issues with toys made of rubber/latex, you might want to try a masturbator made out of silicone.

si-x inside outSI-X – Inside Out

While the exterior of this toy doesn’t quite replicate a real human mouth, the interior makes up for it. If you turn your SI-X Type F inside out, you’ll notice plenty of bumps and grooves designed to rub against your cock during use. The big test was whether or not the toy actually felt like the real thing. Read on….

In short, I didn’t feel like the SI-X gave the best oral sex experience. Yes, you can feel the textures against your erection while using it, but the material was a little too soft and squishy for the sensations to be overly intense. I suppose that’s a trade off, however, since there’s no way I’d be able to use this toy if the material didn’t stretch.

Probably the biggest drawback was the fact that the back end of the toy is completely sealed. Without a second hole, there exists a vacuum inside the toy, and this – at least for me – makes it more difficult to slide in and out of the interior chamber. I’m tempted to modify the toy with a “backdoor air hole” to see if it makes a difference, but I do enjoy the experience I have while using the SI-X, so I’m not ready to chance wrecking the toy…yet.

si-x sideSI-X – Do you like a tight fit?

The guys who are likely to enjoy this “blowjob experience” are those who like smoother sensations, a tighter “mouth,” and those who love the idea of a mouth becoming a vacuum that tugs on their cock during use.

One other thing: one of the things that appeals to me when using a blowjob simulator is how warm the material gets/stays. Some toys can be soaked in hot water before use and retain a wonderful warmth that is better than anything a certain material or texture can provide. The SI-X didn’t really stay warm long enough after being soaked in hot water, so I can’t really tout that as a feature.

One benefit to the closed end means you can bust a nut inside the toy and not make a mess. Clean up is pretty easy. Rinse the toy in warm soapy water, drain it well, then turn it inside out to give the interior a good cleaning and let it dry completely before reverting it to its normal state. (Just so you know, the company that makes this thing recommends not turning it inside out.)

Want to give SI-X Type F a shot to see if it’s just what you’re looking for? Find this masturbator (along with several other “Types”) at:

*NOTE: Toy Demon is an American company that stocks foreign-made (mostly Japanese) toys for men.

Product photos by AllMaleSexToys

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