Coleman Solar 4.5-Watt 12-Volt Deep Cycle Battery Charger is designed to protect against natural battery discharge and electronic drain in RVs, boats, trucks, or mobile homes, the Coleman solar 4.5-watt 12-volt deep-cycle battery charger keeps the 12-volt batteries in the vehicle charged so you can run small appliances such as fluorescent lights, GPS devices, coolers, small TVs, or laptops. The solar charger provides an immediate trickle charge when exposed to daylight, even on cloudy day.