The Extensor Blue The Xtensor was designed to strengthen the muscles on the back side of the hand to correctly counteract the gripping actions your hand goes through every day. Exercising with The Xtensor strengthens the muscles that open the hands addressing the cause of hand stiffness not just the symptoms. Do you really like wearing that elbow band? Using The Xtensor strengthens the muscles at the cause of tennis elbow pain.Computer Users Reduce pain and stiffness in the hands and wrists due to prolonged use of the computer by exercising the muscles that open the hands. Dental Professionals Holding dental instruments for extended periods of time creates repetitive stress in the hands and wrists of dental professionals making job performance unbearable at times. Strength and flexibility exercises designed to rebalance the muscle dynamics in the hands and wrists have proven to be highly effective. Reduce hand stiffness, wrist pain and have a better golf game by strengthening the muscles that open your hands.