Energizer ENC4A 4 Amp Battery Charger with LCD + Battery Maintainer 6/12V - 9 Step Smart Charging Technology Will Improve Your Battery's Life Cycle for Car, RV or Boat 4 AMP FULLY AUTOMATIC BATTERY CHARGER WITH LCD DISPLAY- Perfect Car Battery Maintainer for RV, Boat or Car Battery Charger. The built in LCD display will provide you with accurate status and battery voltage measurement AUTO VOLTAGE DETECTION- detects 6 Volt or 12 Volt batteries, charges and maintains them. Built-in circuit protection guards against overcharging, reverse polarity or short circuit. 9 STEP SMART BATTERY CHARGER- This battery charger helps keep your battery lasting longer then simple chargers BATTERY MAINTAINER- Automatically adjusts the amperage rate to charge and maintain batteries 5 YEAR WARRANTY- Includes a five year, repair or replace warranty and specialized customer service & technical support via email phone or chat. From a brand you can trust! ETL Approved under UL std 1236 and CSA C22.2