Relief Pak® moist heat packs and covers are a simple and effective method of applying moist heat. The moist heat packs provides 30 minutes of therapeutic moist heat to soothe discomfort from stiff neck, backache, arthritis, sprains and bruises. The pack can be heated in water on a stove, in a microwave or in a heating unit. When treatment is complete, the pack can be stored for future use. Always apply moist heat pack with a Relief Pak® cover or a heavy towel completely wrapped around the pack.