Thermite 2.0 vest provides up to 8 hours of heat and is perfect for staying warm during any cold-weather activity. Two-sided pile fleece provides insulating properties without weight; and its hydrophobic attributes hold less than 1 percent of its weight in water. Retains insulating properties even when wet. Polyester fleece resists pilling and has a honeycomb design structure. Four Microwire™ heating zones: Chest (2), Back (1), Neck (1). Core fibers help conserve heat and wick moisture away from the body. Mid-layer or outerwear piece that can provide heat up to 8 hours. Battery Integrated Temperature Controller. Gerbing 7V Battery Heated Jackets & Vests Include:. 7V 3400 mAH Rechargeable Lithium-ion Battery Pack (25.16Wh). Wall Charger. Detailed Instructions. Gerbing Lifetime Warranty.