Can be used cold or hot. They are reusable.
Nexcare™ Reusable Cold/Hot Pack is one-stop shopping for first aid pain relief! Use it cold from the freezer for pain, swelling, bruises or sprains. Use it warm from the microwave to soothe muscle aches and stiffness. Nexcare Reusable Cold/Hot Packs come with a protective cover for greater comfort and an attached elastic band to help hold the pack securely in place.