PERFECT BASE LAYER - The revolutionary design of the IconX Heated Core Vest puts the heat next to your skin; Cold impacts your performance mentally and physically, but IconX Heated Core Vest allows you to stay in the field in tough winter conditions PREMIUM WARMTH - The Pnuma Outdoors IconX Vest boasts 3 different heat settings that provide incredible, sustained warmth with no bulk and complete freedom of movement in any condition; The LED heat level selection button is waterproof and easy to access BATTERY POWERED - This Pnuma Outdoors IconX Heated Core Vest is powered by a rechargeable 7.4V Lithium-ion battery (wall charger included); This battery provides approximately 6 hours of performance at low settings generating 100 degrees of heat GREAT DESIGN - This Pnuma Outdoors Vest feature an athletic fit for easy layering; Strategically placed heating zones provide key muscle support and thermal regulation; USD output on the battery can be used to charge a mobile device SUPERIOR FABRIC - The IconX Vest is crafted of high-quality wicking HydroWick fabric that is knitted with hollow fibers; Also, the fabric is treated with SilverStrike - this technology prevents smell caused by sweat to provide freshness in the field