RBC23 equivalent. Four 12V 7AH packs, bound and connectorized. 12 Volt SLA UPS Battery. Fits models; APC SmartUPS 1000R2BX120, APC SmartUPS 1000RM2U, APC SmartUPS 1000RMNet, APC SmartUPS 1000RMUS, APC SmartUPS A1000RM2U, APC SmartUPS1000RMUS