This Polymer Zipper Sweat Vest for men TRAPS THE HEAT around your core and enhances natural perspiration 3x times more than normal gym clothing. Boost metabolism, enhance calorie burning, get rid of toxins and make every workout more satisfying. This vest was carefully designed to help you smash your fitness goals FAST. Our all new Polymer Zipper Sauna Vest is made from ultra-advanced spandex and polymer fabrics that turn up the heat IMMEDIATELY and get you on the fast-track to your best body.