Description The item is designed to strengthen the forearm, wrist, and fingers. We designed the device to support your forearm and wrist for maximum safety and comfort, while you target train the identified muscles. Simple to use, just rock the wrist back and forth to build strength day by day. Great training tool to build hand and arm strength, definition, power and flexibility; Variable resistance adjustments allows you to measure your progress, and the adjustable grip delivers optimum performance. Features - Color: Black. - Material: Spring steels, ABS. - Size: About 20 * 10 cm/ 7.87 * 3.94 inch(L*W). - Compact and lightweight, strengthen your forearm and wrist force anytime, anywhere.