The moist heat packs provides 30 minutes of therapeutic moist heat to soothe discomfort from stiff neck, backache, arthritis, sprains and bruises. Always apply moist heat pack with a relief pak cover or a heavy towel completely wrapped around the pack. Pack - half size - 5" x 12" - case of 12. The pack can be heated in water on a stove, in a microwave or in a heating unit.