ProMariner Advanced Electronic, Fully Automatic 3-Step Marine Battery Charger 2 Bank; 20 Amp Distributed On-Demand Charging - Automatically senses and distributes a full 20 amps to any one bank or combination of all banks. Faster Charging - 2 to 3 times faster than traditional battery chargers with true 3 step charging technology. Each step is electronically controlled for the fastest charge. Professional Performance - 100% battery charge guaranteed. 100% charging output with AC power as low as 90 VAC while using long extension cords at the dock, lodging site or home. Proven to condition and extend the life of your batteries. Compact Lightweight Design - Rugged Space Saver all aluminum housing is half the height of leading traditional chargers. Unit is not potted and is completely serviceable for lifetime of use under ProMariner's lifetime repair guarantee. Easy Operation - Pre-wired for easy installation. On-board Push-to-Test charge level and mode indicators. Internal battery selection-lead acid, gel or AGM compatible. ProMariner's advanced electronic technology will deliver 2 times the amps to your batteries in the same amount of time when compared to leading traditional linear chargers.