-Types of materials used, Metal, PP, TPR, foam and NBR plastic, made of spiral spring resistant steel. Constructed with the best quality materials, reinforced and reinforced to last a long time. . - Pure design, soft foam handles provide a comfortable and comfortable absorbent grip, prevent injury and long-term resistance in hand training, climbing, weight training, weight training, exercise and better adherence to the gym. . - Effectively finger, grip and forearm. Forearm training provides grip, dramatically increasing the speed of the forearm muscles and hands for optimal performance and mobility. The forearm grip is ideal for improving endurance, power and speed in wrists, fingers and forearms. - Ergonomically designed to fit small and large hands. Perfect for men, women, seniors and teenagers. Ideal for rock climbers, bodybuilders, golfers, surfers, tennis players, drummers, guitarists, pianists, masseurs, baseball players and violinists. Also useful for people with arthritis, tennis elbow, rheumatoid arthritis and carpal tunnel syndrome. . - Usually these are small devices, so you can use them whenever and wherever you want. Small fitness instructor for training your hands and forearms, ideal for strengthening your grip and toning your forearms. .