As long as you use a lubricant (spit will suffice), the bulb ****** suckers will stay on once youve used the bulb pump to get them to adhere to your nipples. With regard to the vibrating element of the product, I could take it or leave it. This was my first *** toy that I purchased and the only complaint I have with it is that the plastic tubing between the 2 ****** suckers should be longer. Unfortunately, I do not look like the woman on the package with the fake boobs so when I lie down, my ******* fall to the side like most natural ******* and I had to lie on my side to bring my ******* closer together so that the suckers could stay on both nipples. Other than that, the product worked well.