Good. The earplug is really small, and you can press in the ear channel to long. Getting i out was a struggle, so be careful. The function of the earplut is in general good, but you need to ensure it to sit well or the noice cancellation will be reduced.
Crazy good price for these bad boys. Tested them with over-the-ear headphones (cranked way up) and they work great. Fast shipping too.