Made out of Heavy duty nylon with 2” Loop strap. Inside bottom padded straps has thick heavy duty, high density rubber to support and cushion the arms during use. Side straps have been lined with a plush nylon fabric that protects the arms and makes the Ab-Strap easier and more comfortable to use. Put arms through loops and grab straps to do hanging abdominal exercise. Do knee-ups, leg-ups as well as rotational drills.