New better fit for more targeted relief! Patented heat cells for deep penetrating heat. Advanced back pain therapy. Up to 16 hours pain relief. Clinically proven to relax tight muscles and enhance flexibility & mobility. Provides up to 8 hours of heat while you wear it plus 8 hours of pain relief after you take it off. Odor free, discreet and stays in place. Air-activated, one-time use. Questions? 1-800-323-3383. For most recent product information, visit www.thermacare.com.