TheraBand Professional Latex Resistance Tubing with Soft Handles for Physical Therapy, Pilates, Yoga, At-Home Workouts, and Rehabilitation, 50 in, Black, Special Heavy, Advanced Level 1 Exercise & strengthen muscles in the upper & lower body to build strength, increase motion and improve conditioning Large soft grip handles are easy to slip over feet & ankles to deliver an effective lower body workout ideal for conditioning & rehabbing muscles Color-coded Progressive Resistance system allows users to recognize improvement as it happens, as you grow stronger you can move up to the next color Rehabilitate muscles through simple yet effective workouts to increase strength & improve motion Special Heavy Black Tubes are the sixth of eight levels of resistance and great for rehabilitation and higher level resistance, they offer 7.3 lbs. resistance and 25% increase from preceding color at 100% elongation and 10.2 lbs. at 200%