Lightning X instant cold packs are perfect first aid devices for cold therapy designed to reduce swelling and inflammation and relieve pain in the event of an injury or emergency medical situation. Unlike Other cold packs that require prior freezing and refrigeration, instant cold packs can be activated with a simple squeeze to reduce the temperature of the contents inside the pack to approximately 35°f for 10 to 15 minutes. Our cold compress packs are easy and quick to activate. Just shake the contents to make sure the content is evenly distributed inside, then just give the pack a squeeze. After mixing the contents gently, the cold pack is now activated and will begin rapidly dropping in temperature. Lightning X instant ice packs are disposable are a must-have addition to any first aid kit. Compact in size, the instant cold pack is perfect for sprains, strains, bumps, and minor injuries. Perfect for travel, sports events, and other outdoor activities. Each CP100 cold pack measures 4.5 inches tall x 7 inches wide, and comes in a box of 20.