The Ring RSC804 is a 4A smart charger and battery maintainer suitable for 6V and 12V vehicles and recommended for START/STOP batteries. Compatible with lead acid, gel, calcium, EFB and AGM batteries. Keeps batteries in good condition without risk of overcharging. One button operation and large LCD backlit display for ease of use as well as reverse polarity and short-circuit protection for safety. Connect and be sure with the charger adjusting automatically to long-term maintenance mode when the vehicle's battery is full. For long term connection.