16 hours of pain relief. Deep muscle relaxation. Odorless. Non-medicated. Deep muscle relaxation. Air-activated, one-time use. Up to 16 hours of pain relief. Up to 8 hours of heat plus an additional 8 hours of pain relief once the product is removed. Please read ALL instructions and warnings before use. To reduce the risk of burns, fire and personal injury, this product must be used in accordance with the warnings and use instructions. Storage: Store in a cool place. Avoid direct sunlight, excessive heat and low humidity. Open the plastic wrapper when ready to use. Peel away paper to reveal adhesive side. Place on area of pain with adhesive side toward the skin. Attach firmly. Do not use for more than 8 hours in a 24-hour period. The product may take up to 30 minutes to heat up. Provides temporary relief of minor muscular and joint aches and pains associated the overexertion, strains, sprains and arthritis. ©Walgreens Co