Beginning with the sound it is spectacular the levels of low and treble that allows you to use it is spectacular, its construction is of very good quality. This is an extremely well made product, very strong but still a comfortable material. Bought model# PSWBT550. Not enough compression for the gym, and a bit odd to wear it (showing prominently) under a shirt (maybe some people would like that. They work well and can be rinsed out and are extremely comfy. This luggage carrier appeared to be fantastic by its description and reviews in December, so we purchased it for our trip. Zero issues with:- bluetooth connectivity- charging, I drop the whole case on the charging pads- sound during calls, nobody knows Im using them until I askI appreciate the portability. They do make a bit of extra noise as you walk on hard smooth surfaces. They work great and I like they fold down and out of the way. Ive had some for several years that I am STILL wearing.