Product Details This compact 2-in-1 device does double duty as both a power pack that charges your smartphone and a handwarmer with a maximum temperature of 113 degrees to keep your fingers toasty. Specs Output: 4400 mAh. Run time: 6 hours of continuous heat. Dimensions: 3.72"L x 1.76"W x 0.9"D. Weight: 5.22 oz. Construction Lithium batteries included. Additional Features Compact design fits in your pockets easily. One mini and one standard USB port for charging. Includes USB charging cable and soft carry pouch. Delivers a full charge to most smart phones, MP3 players, cameras and other USB-powered devices. Imported. Questions? Chat with an Expert