Strength starts at your fingertips! A strong grip is essential in just about every sport. Numerous products exist to build your grip strength, but you would never think of only training your biceps & never train your triceps. Hand X Band™ was developed to exercise your extensors, the muscles that open your hand. Hand X Band™ exercises the abductors to your grips' adductors, your antagonist muscles to your grips' agonists.