Uses usb to charge and works great, a little tricky to get the sets to stand on it right at first but once you do it does the trick! I tip my hat to Samsung. Maybe not as supportive as Tevas, and the jury is still out on how long they will last. Very very soft and comfy! So I do not mind replacing them. These babies fit perfectly, heck maybe a little better, than the originals. The first pair I had for over a year, & at my fault I pulled the aux by the cord at the end of my shift to take them out, causing one of the cords to break resulting in one ear bud not working anymore. Super flattering on the bust And back. However the doors are hard to align properly. Flojos I might go to flip-flop you cant go wrong very comfortable.