ThermaCare Lower Back & Hip heat wraps are specially designed to fit your back and hip area, flexible enough to move with you while still staying securely in place. Patented heat cell technology penetrates deep into tissue to target pain and accelerate healing for up to 16 hours„that's 8 hours of heat while you wear it, plus 8 hours of relief after you take it off. ThermaCare Lower Back & Hip heat wraps deliver heat deep into tissue, warming the muscle right where it hurts„to relax, soothe and unlock tight muscles. * Use As Directed Delivers heat deep into tissue Stops pain and accelerates healing Up to 16 hours of heated pain relief