The Therall Heat Retaining Back Support is constructed with four-way stretch material for light compression. Material has ceramic fibers that retain heat and slowly reflecting it back into the joint and surrounding tissues. The result is therapeutic heat penetrated deep into the aching joint, muscles and surrounding tissues to provide long-lasting, soothing relief. Support promotes healing by increasing circulation around the tender joint and improves joint mobility to allow for faster return to daily activities. Can be used with Therall Body Warmer Patch (sold separately) for over 12 hours of soothing heat therapy.