No water is needed. This pack produces its own moisture using humidity in the air. There is nothing to boil or microwave. When to use your Thermophore Automatic Moist Heat Pack: Use your Thermophore pack at the first sign of joint pain or muscle spasm. Use it for the pain of over-exertion from sports, gardening or household chores. Muff (8 inches by 17 inches) rolled, for stiff and painful hands. Petite (4 inches by 17 inches) for TMJ, neck and sinus.
Use your Thermophore Hot Pack carefully. To work properly, it must be extremely hot. Do not use over insensitive skin or in the presence of poor circulation. Do not use if swelling is in evidence. People with diabetes should be especially careful when applying heat. Children and those who are incapacitated should be supervised in the use of the hot pack and should not be left unattended. Temperature is sufficiently intense to cause burns. Check skin frequently. Do not use on infants. Do not use a hot pack as a bed warmer or foot warmer; it gets too hot to be used for these purposes. Excessive treatments may bring adverse effects. Should unusual symptoms appear, discontinue use of the product and consult your physician.