The Best Power Technologies Fortress LI1800, LI 1800 is a UPS system that requires a 6V 12Ah AGM replacement battery. The compatible Universal Power Group replacement is the UPG UB6120 6V 12AH F2 AGM Battery (UB6120), a 6V 12Ah AGM sealed lead-acid battery. This battery delivers up to 72 watts of standby power. It weighs 4.18 lb, uses F2 terminals, measures 5.94 L x 3.7 H in, and has left polarity. This is a direct drop-in replacement for the Best Power Technologies Fortress LI1800, LI 1800 requiring no modification to the device.
