Charge your CS FREE anywhere using the 12V auxiliary battery. The CTEK USB-C charging cable with clamp connection was developed in Sweden. It allows for quick, safe, and easy charging of the CS FREE via the 12V auxiliary battery. The clamps can be connected to the vehicle battery, enabling charging without a mains power connection. Simply attach the black and red clamps to the corresponding positive and negative terminals of the auxiliary battery, and insert the USB-C plug into the charging port of the CS FREE.