The Core Pain Remedy TENS System by Core Products uses wireless technology to stimulate nerves and block pain signals. The system is used to relieve sore muscles and aches that are caused by strain. A long day at the office or a strenuous workout can cause reoccurring pressure to particular areas of the body. The Core Pain Remedy system allows the user to apply a reusable 3"x5" body pad electrode to the affected area and choose between 20 different intensity levels. The muscles are gently massaged, allowing soreness and stiffness to subside. The controller has a timer that allows up to three hours of continuous stimulation. The system is powered by a rechargeable lithium battery and comes with a charging kit. An auto shut-off feature keeps the system from running too long.