Exercise your hands and fingers with this Prokyde α-Trainer Power Hand Grip to improve their strength. Foam Handles – The foam handles of this power grip help you train without straining or developing calluses on your hands. Ergonomic Design – This power grip is ergonomically designed to perfectly fit your hands for a comfortable workout. Ideal Usage – Use this hand grip to improve the strength of your forearms, wrists and grip, as well as to improve the dexterity of your fingers. Single hand power grip with triple steel tension coil build and foam handles with Ergomonic design to fit your hand for a better workout When use, you use single hand or both hands hold the hand grip tightly and strongly force the two handles to close up, then release. This power grip helps to condition and strengthen your hands, wrist and forearm muscles.