No, you don't have to add any water to our covers. The special Moist-Sure™ fleece cover absorbs moisture from the atmosphere to generate a light layer of moisture on your skin. You don't need to be dripping wet for effective moist heat therapy - just a light layer of water vapor is all you need, and most homes have plenty of humidity in the air to provide the necessary moisture.

It helps to add more moisture to the cover if you store the Thermophore® cover in a humidified room or in the laundry or bathroom - any location where there is plenty of moisture in the air when it is not in use.

Often, just washing the cover will allow the fabric to re-absorb plenty of moisture. There are no chemicals to wear out, and no special treatment of the fabric is required - it can be washed and dried as needed. For arid climates, areas where the air gets very dry for part of the year, or homes where heavy use of heating or air conditioning systems dries the indoor air, we now have a Moisture-Plus™ cover as well. Included with our Thermophore Classic™ Plus and MaxHEAT™ Plus styles, this cover has a vinyl-lined pocket to let you safely add a damp cloth and increase the available moisture. When atmospheric moisture just doesn't seem like quite enough, you'll love the Moisture-Plus™ cover

Each Thermophore® unit has a specially-woven Moist-Sure™ fleece cover. Between uses, this cover traps moisture from the atmosphere in the air spaces between the textile strands. Although the fabric does not feel wet, the application of quick, intense heat will generate this moisture into water vapor to increase the benefit of heat therapy.

When activated, the Thermophore® heating unit becomes intensely hot very quickly. Through what is known as "hygroscopic action", the moisture moves away from the source of heat to the cooler body tissue. When properly applied, a light layer of moisture is produced between the Thermophore® unit and the body, to allow a deeper, more effective transfer of heat into painful areas.

Thermophore Classic™ Plus and MaxHEAT™ Plus systems include a Moisture-Plus™ cover that utilizes atmospheric moisture, but also allows you to safely add a damp cloth for additional moisture.

If you live in a dry climate or frequent use of the heating/cooling systems in your home dries out the indoor air, adding the Moisture-Plus™ cover will insure the ultimate in moist-heat therapy!

After placing the hot pack unit inside the cover, plug the unit in and lay it out flat on a glass or Formica table or counter top. Either hold the switch down (if you are using the Thermophore Classic™) or push the "on" button (if you are using the MaxHEAT™ style).

Let the unit warm for about 5 minutes to activate the moisture in the fleece cover. When you pick up the pad at the end of 5 minutes, you should see tiny moisture drops on the glass or Formica surface. If you run your hand over the surface, you can feel the moisture and see streaks of water. If you live in an area with a dry climate, or frequent use of the furnace or air conditioner makes the indoor air too dry, you may need to use our Moisture-Plus™ cover. It will utilize atmospheric moisture but also has a separate vinyl pocket that allows you to add a damp cloth for added moisture.

We recommend using the Thermophore® directly on the skin, if possible so that the moist heat can penetrate most effectively and deeply into the tissue. Using it over pajamas or a shirt will also work if that is more convenient for you.

Metal buttons, clips or buckles on clothing under the Thermophore® may become quite hot, and should not be allowed to contact your skin directly until they have had a chance to cool.

We recommend that you do not lay on top of a Thermophore® because it will reduce the effectiveness of your moist heat therapy and may damage the components inside your Thermophore®.

The Thermophore® pack treatment is so soothing and relaxing that users often doze off as their pain and tension ease. If the user does fall asleep while using the original Thermophore® Automatic Moist Heat Pack™, their hand will relax, automatically turning the unit off. No other product has a safety switch quite like the Thermophore® Automatic Moist Heat Pack™.

Our Thermophore® Arthritis Pad™ offers the quality and intense heat users have come to expect, plus the added convenience of a pre-set control to leave your hands free. Users turn the heat on and off with simple push-buttons to control the level of heat to their personal preference. If they happen to doze off or become distracted during treatment, the unit automatically shuts off at the end of the current 20-minute cycle.

To relieve aches and pains, it is necessary for the heat to effectively transfer deeply into body tissues. To make the Thermophore® pack more efficient, we have positioned weights to cause the Thermophore® pack to conform to body contours. This reduces air spaces between the Thermophore® hot pack and body, so more heat is transmitted to the body tissues. Ordinary stiff plastic heating pads leave air pockets, which result in an uneven transfer of heat.

The warning not to sit or lie on top of your heating pad is required by UL Standards, the guidelines used by the industry for testing and approval. It must be included on any product that is currently tested and approved for sale in the US by UL, ETL, or any other Certified Testing Lab.

The Thermophore® is constructed with heater wires in a fabric's foundation. Folding or lying on top of the unit traps and intensifies the heat at "pressure points." The Thermophore® is also able to trap more moisture from the atmosphere when it is not insulated between your body and the cushioning of your furniture or bed. In addition, our units reach a much higher temperature than ordinary heating pads and it would be possible to damage your skin (or your furniture) by trapping and intensifying this heat.

Compressing the Thermophore® when it has become folded or bunched under your body can also damage the special metal strips inside, and they serve several functions. They hold the heater wires in place throughout the entire area of the Thermophore®, help distribute the heat and retain the heat level when the switch is shut off, increase the production of moisture, and make the heating unit mold against the contours of your body to make good contact for even transfer of heat. Lying or sitting on a Thermophore® will often mangle these strips, reducing their effectiveness.