Core Prodigy Superhuman Grip - Adjustable Hand Strengthener/Gripper Strengthen and Train Fingers, Hands, Wrist and Forearms. Ideal for Athletes and Fitness enthusiasts want a stronger grip or to help recover from an injury. By slightly squeezing on the handle and loosening the dial, the spring can be moved to one of four settings. The Superhuman Gripper offers an adjustable resistance range from 22lbs to 70lbs. Super Durable Construction and Workmanship. 100% Money Back Guarantee. By Fitness Product Leader - Core Prodigy