Calcium ammonium nitrate and water combine when you squeeze this pack so it becomes cold within a matter of seconds. Apply cold pack for relief of pain and swelling caused by sprains, strains, contusions, minor burns, toothaches, insect bites, and other minor injuries. This disposable ice pack offers immediate relief, making it an essential addition to your first aid kit. - Carestock instant cold compress provides fast and effective relief from minor pain and swelling caused by various injuries and discomforts.. Terrific for sprains, strains, contusions, minor burns, toothaches, insect bites, and more, making it a versatile addition to your first aid kit. Activate the instant cold compress with a simple squeeze and shake, offering immediate therapeutic treatment without the need for refrigeration.. Designed for one-time use, this disposable ice pack is a hassle-free and essential companion for pain relief. 5 x 7 inches.