Everlast's Adjustable Grip Strengthener improves your forearm muscles and hand endurance. This hand strengthener features a durable and rubberized grip for a comfortable squeeze as your fingers, thumb, and palms toughen up. Keep your routine moderate or amp it up with adjustable resistance, from 20 to 90 pounds (9 - 41 kgs.) Turn the adjust dial to change the resistance level. Keep track of your repetitions with the built-in counter. While great for strengthening the hands, this strengthener also assists the wrists and forearms.