Abstract: A microwavable heat releasing and absorbing composition comprises paraffin wax, distilled water, polyacrylamide, mineral oil, glycerin, polypropylene glycol, acid and corn starch. By variation of the relative ratios of the components, the composition can take on a variety of consistencies and viscosities. The composition is capable of retaining its temperature for an extended period of time despite surrounding variations in temperature. It is also capable of maintaining its pliability and consistency over a wide range of temperatures. The composition has a high vapor point and is well-suited for heating in a microwave oven, or cooling in a freezer. The composition when placed in a suitable container can be used in hot-and-cold packs, as well a variety of other applications. Preferably, the container is enclosed in a vinyl package with transverse ribs.