APC BY SCHNEIDER ELECTRIC Replacement UPS Battery For Mfr. No. SUM1500RMXL2U, SMT2200RM2U, SMT3000RM2U, SUM3000RMXL2U, 48V DC - 426P04|RBC43 - Grainger
APC SmartUPS 1500 Battery by AtBatt
MIGHTY MAX BATTERY 12-Volt 9 Ah UPS Battery Replacement for APC BE550G ML9-12101 - The Home Depot
How to replace an APC Smart-UPS rack mount battery - APC UPS Blog - ExcessUPS.com