The Best Power Technologies FE12.5KVA is a UPS system that requires a 12V 75Ah AGM replacement battery. The compatible Universal Power Group replacement is the UPG UB12750 12V 75AH I6 AGM Battery Group 24 (UB12750), a 12V 75Ah AGM sealed lead-acid battery. This battery delivers up to 900 watts of standby power. It weighs 50.7 lb, uses I6 terminals, measures 10.24 L x 8.29 H in, and has left polarity. This is a direct drop-in replacement for the Best Power Technologies FE12.5KVA requiring no modification to the device.