The perfect size to use in several locations - perfect for covering your back. Find relief from strains, sprains, tendonitis and other injuries. Unique strapping system securely fastens anywhere on these hot and cold packs. Non-toxic gel is biodegradable and retains therapeutic temperatures longer. Soft, plush "frost-free" cover protects your skin. Store in the freezer; stays soft and pliable. Heat in microwave.