Thermal and lightweight materials to fit under jacket or used by itself. Heated jacket liner is wired directly to your bikes battery allowing for near endless warmth; if your bike can run, you can stay warm. Jacket liner comes with necessary wire harness for wiring to your bikes battery. When more than just core warmth is needed, connectors at the end of each arm allow for easy connection to firstgears heated glove liners. Connect to your vehicles 12v battery system. Dc:12v, draw: (75)w.