CyberPower RB1290X6B Replacement Battery Cartridge - 6 X 12 V / 9 Ah Sealed Lead-Acid Battery, 18MO Warranty

Easily replaceable by the user In terms of cost per watt hours, it is an inexpensive choice providing efficient power 12 V DC battery ensures a steady and constant electric supply to UPS It can be chained with multiple battery packs for extended run operation