APC RBC 11 Battery.
Got this at an office, selling it because I don't have any need for it and I'm unsure if it works because I don't have the necessary equipment to test it out.
Premium Power products compatible battery replacement for the APC RBC11, SU1400XLTNET, SU1400RMXLTNET, SU2200, SU2200NET, SU2200RM, SU2200RMNET, SU2200RMXL, SU2200RMXLT, SU2200XL, SU2200XLNET, SU2200RMXLNET, SU2200RMXLTNET,SU2200XLTNET, SU3000, SU3000NET, SU3000RM, SU3000RMNET, SU24XLBP, SU48XLBP, SU48BP