I bought these to go in my wedding dress.  The dress fit perfectly besides being a little large in the bust.  Instead of having it altered... I purchased these to 'fill it up a bit'.  They did the trick.  I danced the night away, and they stayed perfectly in place the whole time.  They definitely need a thin sock or hose material around them because they do create quite a warm environment.  I didn't notice, and it didn't matter in my case, but they do have nipples (just in case someone needed to know and didn't notice!).  I've noticed other reviewers mentioning their 'full coverage'... mine stayed nicely tucked towards the bottom of my boobs.  Maybe since I have a fuller chest already, they didn't seem to cover too much.  Maybe with a smaller chest they would sit practically on the entire thing.  I wouldn't say they provide much size or lift, probably more like a little more fullness.