What is the Full Back Warmer/ Cooler? Fabric pack that contains sterilised natural wheat which conducts heat & cold. Can be put in the microwave or freezer to provide a hot or cold pack. When can I use it? This pack opens out to cover the whole back giving gentle warming heat over a large area. Suitable for back pain relief, Lumbago, Sciatica, Facet Syndrome, Degenerative Disc Disease, Herniated Disc, Slipped Disc. Size Weighs 2.5kg & measures 51cm x 43cm. How does it work? WHEATeeze Packs contain specially selected high grade natural wheat which has been treated & cleaned. When heated in a microwave oven they generate a comforting moist heat that is very therapeutic. The degree of moisture is dependent upon the atmospheric humidity & the amount of use the pack receives. If increased moisture is required then a cup of water in the microwave whilst heating the pack is recommended. The WHEATeeze Relief Packs can also be stored in a freezer & applied directly to an area of injury to reduce swelling, without the risk of ice burn, thereby accelerating the healing process of sporting injuries.