The HT Heat Tech Vest features Alpinestars Heat Tech System which distributes perfectly balanced warmth in the coldest of conditions. The smart system has a double system for optimum performance in cold weather; a manual control via an LED button with three pre-set heat settings AND an automatic heating control system. The automatic heating control system has a temperature sensor embedded inside the vest to continuously check the rider’s temperature in order to provide and maintain the pre-set heating temperature for supreme riding comfort. Smartphone Alpinestars Heat Tech App (as used on Alpinestars Heat Tech gloves) for turning the vest ON/OFF and to precisely set and control the internal temperature via a Bluetooth® connection. Dual power: the vest can be plugged to the bike battery or used with the high performance 12v Lithium Battery (included with the vest) for reliable, long-lasting power to the Alpinestars Heat Tech System.