Why should you buy an Energizer battery charger? The Energizer ENC-4A 4 AMP battery charger/maintainer features 6 volt and 12 volt charging selectivity, with a 9 step smart charging technology that will improve your battery's life cycle. Use for battery maintenance at 2AMP or rapid charging at 4A, great for charging RVs, specialty vehicles, antique and classic cars, marine deep cycle batteries, motorcycles, lawn mowers, ATVs, snowmobiles, personal watercraft and more. Maintains battery charge in stored vehicles and battery applications. The built in LCD display will provide you with accurate status and battery voltage measurement Fully automatic, provides a charge when needed, stops charging when battery is fully-charged or topped-off. Built-in circuit protection guards against overcharging, reverse polarity or short circuit. We believe in our quality and have the warranty that proves it - 5 Year warranty.