Can be used either hot or cold. Remains flexible when frozen. Retains temperature longer. Reusable, durable and long-lasting. Ice pack/heat pack is in a child-friendly shape used to minimize pain and swelling from a procedure or everyday bumps, bruises or injuries. Freeze for cold, microwave or boil for heat. Use cloth side to skin and apply as recommended by your doctor. Customer personalization available on case packs.