The premium Lithium-Ion batteries are crafted for peak performance, ensuring lasting power and durability. Compatible exclusively with Mobile Warming 7.4-volt Gloves and Longman Baselayers, these batteries provide hours of warmth and comfort. Sold individually, each battery boasts a rating of 7.4 volts with 2,000mAh capacity, and requires 3-4 hours to fully charge at 8.4 volts input. Dimensions measure 2.0 inches x 1.7 inches x 0.35 inches.