This cold roller ball massager will help relieve sore muscles. Roll on trigger points, relieve a cramp or use for deep tissue massage. Also helps to relieve the pain from plantar fasciitis. Simply remove from the rubber holder and place in the freezer for 2 hours. The cooling gel will stay cold for up to an hour. Safe to use over and over again. Portable for easy traveling. Due to risk of injury, we do not recommend using as a hot massager. By Trademark Innovations.