Keep your hands warm and comfortable with the ThermaCell Heat Pack Rechargeable Pocket Warmer. This set comes with two units of hand warmers that can stay effective for up to 6 hours. They are perfect for outdoor activities like hunting or any other outdoor sports during the cold season.These hand warmers are from the brand Thermacell and come with a California Prop 65 Warning. The warning cautions against exposure to chemicals that can cause cancer or birth defects. These warmers are in the categories of Hand & Body Warmers, Hunting Accessories, Hunting, and Sporting Goods, making them a great addition to your outdoor gear.