Elastomed balls with a smaller ball inside for alleged vibratory action. Good for reminding me to do Kegels. They are heavy enough to present a challenge to my PC muscles but not so heavy that I can't hold them in. I can sort of feel the vibrations if I have only one ball in and one out (right up against the labia) and I walk around, but it's nothing to get blown over by. You're supposed to do Kegels for about 10 minutes a day to help strengthen PC muscles but these will motivate you to do much more than that. If you do choose to keep them in for an extended period and your PC muscles aren't all that tight yet, make sure to hold on to the string or just take them out when you go to the bathroom. Keep the toy cleaner handy as well.

I agree with other reviewers that there's a naughtiness to just walking around with something inside you. I can get housework or other work done and have a very pleasant rebellious sensation at the same time. I'm planning on trying them out at work. Imagine sitting in a long, boring meeting with the boss you hate (or even one you like) and smiling with the secret knowledge of playing with sex toys at work, all under the guise of doing Kegels.

The hypoallergenic nature of the material is helpful. I have very sensitive skin and have not been irritated by these at all so far, maybe 10 hours of use total. I even fell asleep with them in at one point, and aside from some annoyance that there was something inside me waking me up, my privates are not on fire as they would be with even brief exposure to other materials.

Lube helps get them in the first time, but I haven't really needed it since then. My body seems to want these things inside me.