The ThermaCare thermal patch provides relief from muscle and/or joint discomfort associated with: fatigue, muscle tension, excessive effort, strains, sprains and arthritis. Provides 8 hours of constant heat while wearing it and 8 more hours of relief from discomfort once the patch is removed. Open bag when ready to use (it may take up to 30 minutes to reach proper temperature). Peel off the paper to reveal the adhesive side. Place the product on your knee with the adhesive against your skin. Fix it firmly. Be careful when applying the product; do not overlap heat cells. Do not fold, overlap, or crowd heat cells as this increases the risk of burns. Discard after use. Each thermal cell contains iron (approx. 2g). If iron is ingested, consult a professional immediately. Never heat the product in the microwave or attempt to reheat it by other means, as the patch could catch fire. Products that emit heat can cause burns. Check your skin periodically while using ThermaCare. If you detect signs of irritation or burning, remove the product immediately. If the patch feels too hot, stop using it or remove it from direct contact with the skin, placing it on a layer of clothing. The risk of burns increases with age. If you are 55 years old or older, do not use it while sleeping. Do not put additional pressure on the product. To avoid the risk of burns, remove the product before undergoing an MRI. Do not use it for more than 8 hours in a 24-hour period. Consult your doctor/pharmacist before using this product in case of diabetes, heart and circulatory problems and rheumatoid arthritis. Stop using the product and consult your doctor: If you notice discomfort, burning, rash or other persistent skin changes in the application area. If after 7 days of use the discomfort persists or worsens.