CTEK Cig-Plug (Part No. 56-263) enables charging the battery through the cigarette outlet. It eliminates any hassle, simply charge from within the car, suits perfect for CTEKs battery charger with Comfort Connect, UC 800, US 800, MULTI US 3300, MULTI US 7002, US 0.8, and MUS 4.3. Note that the vehicle needs to have power on the cigarette outlet when not in use. CTEK Cig-Plug fits both 12 millimeter and 21 millimeter outlets and has a maze-like strain relief for the users safety.