Carton of 50 pieces The instant ice pack is a plastic bag filled with water, along with nitrogen salts in a non-woven fabric bag or a plastic bag. Instant cold compress provides immediate cold relief for strains, bruises, sprains, and other injuries, or in insulated shipping boxes to keep products cool during transport. How to use an instant ice pack? The instant ice pack is quick and easy to use. Once the pack is squeezed, it turns into a reusable ice pack for pain relief from bruises, sprains, and shocks. Step 1: Squeeze the pack with both hands (the puffed part of the bag) to break the inner water bag to mix the contents.