I was hesitant about ordering this product without any reviews…it seemed like a fairly reputable company, but I couldn’t find any information about it anywhere. So, I went for it. It vibrates, and well. I haven’t gotten the bullet inside to come out yet, but that’s fine. It can stay. My one and only complaint, which my fiancee laughs at me about, is that the suction cup is ugly to me. However, it works. Not so great on say, an exercise ball, which I might just need to air up more, but on a flat surface…works great. The next concern I had was rejection, and I can say that it stays in very well with or without extraneous…activities, so I am pleased. It’s not by any means a puny plug, so I’d say a generally roundabout medium sized plug. And that’s that.