Adjustable Hand Grip / Exerciser / Strengthener, Resistance range from 22 lbs to 88 lbs. (10-40kg) The bintiva hand gripper features high quality workmanship, with a strong and durable spring that is built to last. Ergonomic design that is made for hands of all sizes, including kids, teens, adults, and seniors, both men and women. Hand strengthener features a wide range of resistance, that makes ideal for those suffering from arthritis or carpal tunnel syndrome, and perfect for rehabalitation from a hand, or finger injury. The hand exerciser is ideal for athletes that want to increase their range of motion and dexterity, it also enhances finger, and hand strength. Like all Bintiva products, the hand gripper comes with a 100% manuafcturers warranty