Great for warming hands, feet, and any body part which experiences cold. This convenient, air-activated 2-piece Heat Pack Hand Warmer Set features ultra thin pads that warm to 65 degrees Celsius/149 degrees Fahrenheit when opened. Heat lasts approximately 12 hours. Keep one in the car and in first aid kits. Outdoor workers, professional athletes, sporting enthusiasts, spectators and anyone wanting safe, natural warmth, can rely on these heat packs.