90% POLYESTER 10% SPANDEX Hook-and-eye closures ensure this waist cincher vest could fit your figure at the most extent.Vest style make sure that this waist trainer won't lose when you take exercise Adjustable strap enable you to adjust the size that you want. Triple rows of hooks & eye closures inner and zipper closure outer, 2 steel bone+3 row hook and easy adjust to fit you well PROMOTES BODY HEAT: Design to make you Sweat like crazy and enhance your workout to achieve your weight loss goals. The Sweat Enhancing Thermal Vest intensifies perspiration in your core more than regular gym-clothing during exercise High Elastic Material:The inside is pure Cotton is very smooth for under clothes. Ideal for YOGA, POSTPARTUM RECOVERY, GYM, SPORTS, BODY SHAPING etc, and guarantees a correct posture during your workouts