These adhesive push up bras are the BEST and an absolute MUST for girls with small boobs!!!!! I have never found anything that works as good as these. I bought them to help me appear more full in my bikini top because I am SMALL chested and it makes me insecure. And they made me look great! The bra stayed concealed perfectly under my bikini top and stayed adhesive ALL DAY LONG for a beach event I went to. Without any wardrobe malfunctions!!!! I had no idea if they were waterproof and decided to test it and they are! Literally stayed put for over 6 hours, in 90 degree Florida heat, excessive sweating, and full submerging into the ocean!!! I swam submerged for long stretches of time, got picked up and thrown into the water by my friends several times, and it did not budge!!! My boobs looked fantastic. For sizing, I am a 34B and bought an A, and they made me look like I was a C. Such a confidence boost!