We all know how much of a pain and waste of money it is to replace batteries. These sandals feel like a hug for my feet! I tend to use the EQ function in the Spotify mobile app for tweaking the overall sound to my taste and that works well for me. Fits great easy to put on ordering another pair The sound quality on these is only "okay," and really not great if you cant get them sealed in the ear. They sound great too. Inspected. The picture shows a cork wedge although the shoe I received has a wood wedge sole. I haven?t charged them since I got them. My hubby LOVES his new boots!