Features: 1. Aluminum alloy construction with reinforced nylon shoulder straps, maximize your bicep and triceps workouts 2. Adjustable nylon clasp shoulder straps, custom for your body. 3. Unique shape design, target at training your arm, pecs and shoulder muscle groups 4. Perfectly supports your elbows, enables to keep the correct posture during curls 5. High-density sponge pads on both sides of the training board, protect the elbow and relieve the pressure of the arm. 6. Ergonomic design fits the human body posture, protects the muscle to the greatest extent, the intensity is no longer big will not injure themuscle.