I checked these were fully charged and replaced them in the headset and hey presto - I was in business. so when one wears out (if it does) Ive got a back up already! This is very different than deeper creases that will occur in a boot as it breaks in over time. Theres no protection from the inside just plastic. Run away from these sandals. If your foot is more on the wide side, these might be too tight for you. I own and use a lot of different ear buds and, low and behold, I ended up with an inner ear infection. Highs and mids are just great and detailed vocals, you never hear harsh trebles like flip 4. I like these shoes theyre pretty comfortable all around except for, as some others have mentioned ,the upper edge of the shoe. The first one we purchased from Wayfair was the wrong finish so our loss because they dont accept returns.