ThermaCare Heat Wrap Pain Relief -Lower Back & Hip are ultra thin wraps that stay warm for up to 8 hours. These pain relieving wraps head straight to the sight of pain.Wraps snugly around the affected area, providing targeted pain relief that penetrates deeply, warming the muscle right where it hurtsWhen worn for 8 hours, can deliver up to 16 hours of soothing back pain relief Applied directly to the skin, allowing you to stay on the move.