The Westone ES49 Custom Ear Plugs are a set of ear plugs modeled specifically for your set of ears. I went to an audiologist who took the mold and sent out for them, I believe that you can do it yourself if you so choose, with the proper equipment needed of course. Since they will be indeed cut for your ear, the ES49s are quite comfortable. They also came with two sets of attenuators, one for louder volume environments, but I generally stick with the smaller ones as I find that they do the job well enough. I use these ears plugs for uses of all types, really whenever I'm in a place where there is loud noise or music. The main uses that I have for mine are for concerts as well as practicing with a band. They not only do a great job of blocking out the sound, but they do so in a way where it is still possible to hear everything going on around you. Before I got my pair of Westone ES49 Custom Ear Plugs I had another pair of Westone's that were generic, and while they do an okay enough job of blocking sound out, the problem was that I couldn't really hear the music very well. With the ES49s it i a whole new ballgame as I'm able to hear each instrument individually without a problem and without blowing out my ear drums. While I believe the price on the ES49s do vary depending on where you go to get them made or if you make the mold yourself, but I did a good amount of research and got the set at a very reasonable price. I'm very happy that I got these as it makes my concert and band practicing experiences much more enjoyable and eliminates my fears when I'm going into a loud music environment...