Constructed of strong metal with comfortable foam padding to prevent the hand from hurting before the muscles are fatigued. Ergonomically designed, it perfect for men and women, seniors and teens Hand grip strength exerciser are used to greatly strengthen your hands, wrists and forearms. As a result,you will drastically improve your performance in terms of hitting,throwing,pulling, pushing, holding and even playing instruments Featuring all metal rings and heavy duty spring, it is designed to endure long term and frequent use They are also an awesome option for stress release providing you with energy and leaving you feeling fresh