Hand grippers are devices that you hold and squeeze while tension is being placed on the hand. They usually consist of two small handles and a large tension spring in the middle. Just like the stress ball, these gadgets are easy to use, portable, and help strengthen your grip more than any other device. If you experience a lot of hand pain, these gadgets are not for you because they usually require a lot of tension and strength, however, there are some adjustable types that allow you to change the level of tension.