Sunforce 52013 1.8-Watt Solar Battery Maintainer (Pack of 2) Each panel creates 1.8 Watts of energy and charges 12V batteries Works with motorcycles, cars, snowmobiles, tractors and more Made of durable ABS plastic and amorphous solar cells For indoor use--solar panels are not waterproof Each unit includes 7.5 feet of wire, 12V DC plug, suction cups for mounting for easy mounting onto windshields, and battery clamps for plugging into cigarette lighter