Ps, these slip ons stay put without falling of etc. I have no issues with battery life, I?ve been ending the day with around 40% battery left. For me, this was no big deal, since my straps were already as shortened as possible. I was able to get them just right on my feet which is the reason they get to stay. Non had these, and all the non thong style shoes in my somewhat uncommon style were ungodly uncomfortable, some, even though they said size 13 didnt even fit my feet. Although they are not noise cancellation, they still block out a good amount of noise just by having them on. The bottom of the shoes are peeling away from the fabric already and have only had them a couple months But DAMN! It wouldnt come up by itself. Sooo comfortable to wear and walk in.