Back pain is often caused by tight, injured or sore muscles. ThermaCare Lower Back & Hip HeatWraps deliver 8 hours of continuous, therapeutic heat and relieves pain for an additional 8 hours after you take it off. In fact, the American College of Physicians (ACP) recommends real heat as a first defense against acute lower back pain. These single-use wraps are designed to provide pain relief at home or on the go.