Sometimes, the simplest things are the best. Pull-ups are a classic way to gain definition in your arms, back and core using your own body weight as resistance. From pull-ups to hanging knee-ups, the Power Up Chin Up is a fast and effective way to sculpt and define. What’s best, it weighs less than a pound, making it convenient to carry with you. Simply attach it to any door and you’re ready to go. Gain definition in your arms, back and shoulders with chin ups and pull ups. Sculpt and define abdominal muscles, obliques, and lower back with hanging knee ups!