Best replacement I could hope for. One of the lids somehow came off and I couldn't put it on properly. There was always bubbles and it just kept popping and eventually I lost it. I was concerned that since these replacements do not have small inserts on the back they would not fit securely, but I was wrong! I think they are more comfortable than the originals because they don't have little notches, they are much smoother. They don't twist or twist, it's a really snug fit.