For a greater fitness chalenge use the Smart Muscle Weighted Vest  by Twist to increase the benefits of you body weight exercises like push-ups, chair dips, squats or lunges.One Size! Adjusts at shoulders and waist to comfortably fit most any adult.  Adjustable weight resistance from 1-20lbs (twenty, 1 lb. weights included  Sweat resistant lining and washable. 40 lb. vest also available  @ $159.95.