Battery is awesome so far. 0 wireless ear buds. Even without using the heel strap, they stay securely on my feet. There is ways to save battery life for sure. Now, no matter what I do it will simply not pair. 0 card and add an extended wire back to the card. Just arrived, and I love them. I personally like the straps loose fitting and these don?t give me much to work with. Perhaps a manufacturing issue with the one I got, or a design flaw, I am not sure. Best value by far!