Power Twister Adjustable 3 Weight-modes,Heavy Duty Spring Chest Expander for Shoulder, Arms and Chest Exercises, Upper Body Training, Forearm Exerciser, Arm Trainer Device 20KG,30KG,40KG 3in1Tension Size One Power Twister bar comes with three weight modes, change the holding position to change the weight. save money and be convenient. From D. I. L original brand Safety Materials Premium quality carbon steel springs and anti slip ABS plastic handle. The handle is treated with anti slip and anti off treatment, fitness while ensuring safety Easy to carry convenient to exercise in office, school, home, travel,etc. Flexi rods are great for