It's silicone, period. Anything silicone for backdoor is best, you want non-porous material. I found an odd quirk with some Tantus toys. Sometimes you'd find 1-2 little flaws in the item, meaning it is not completely smooth and may have an air pocket or little dent. This apparently happened with me and I've found some people who own Tantus toys to have reported similar things. They haven't been noticeable or make the toy uncomfortable but I feel it should be mentioned.

Now the shape of the toy... is a love hate relationship. While I definitely do feel it pressing my spot to a degree, the shape feels all wrong as if the curve is located too high. A flared base is nice, but due to it's curved nature, it will try to screw/spin to the point the curve is pressing away from your prostate due to resistance and the fact that there's nothing to secure the toy short of holding it or sitting on it, kind of a buzz kill when you'd rather focus on other things than constantly having to re-adjust the toy. It happens to me so often that it's made this toy my least favorite. One good thing is the logo is on the base, so you can feel around for that and always know exactly which way to re-adjust it.

I have some good to say about it, it slides in rather easily, the shape is appealing, you could slip it on your finger to use on a partner but you'll lack vibrations however those are disappointing.

Vibrations from the bullet are all not that powerful, it's great if you don't want something intense, but hardly noticeable. I feel it's a cheaply made bullet with a weak motor which takes expensive batteries that do not last all that long. Maybe 5-6 good sessions then they're done.

It's a pretty well made product in sense of material, but in terms of design shape it's my least used toy. It's often collecting dust, if the base was changed a little so it wouldn't slide left or right and press up against your rectum walls instead of prostate it could be a lot better, but I feel there are better toys out there for this kind of use.