Dual Pro Eagle Performance Series with D-Style EZ-GO Portable Battery Charger, 36V/20 Amp Chargers will turn on at extremely low voltage (6 volts on a 36 Volt System and 8 volts on a 48 Volt System) Charger promotes 25% longer Battery life Safe to leave Charger on continuously (24/7) with gfi Outlet or surge Protector Charger turns on and off automatically as needed by the batteries Proven technology engineered and built in the USA