The Lifeline® Instant Cold Pack is compact in size so it can be easily carried in a first aid kit, survival kit, or backpack, while on the road. The cold pack is ideal for providing immediate relief from strains, swelling and headaches. The Instant Cold Pack serves as a great alternative to crushed ice, to relieve physical strains in the field. This product is a "single use" item, so if you have room, add several to your kit! The pack measures only 4" wide x 6-1/2" high x 3/4" thick, and weighs only 4.7 oz.