The Chattanooga Original Hydrocollator Moist Heat HotPac has been the first choice for physiotherapists, physicians, chiropractors, athletic trainers and kinesiologists for over 60 years. The benefits of moist heat therapy over dry heat are well established for pain relief due to arthritis, myofibrosis, back pain, muscle strains and spasms. Each all-natural HotPac contains bentonite, a natural hydrocolloid filling, and is wrapped in a woven cotton blend. Delivers up to 30 minutes of deep, soothing relief and can be reheated as needed.