CyberPower BP36V60ART2U Extended Battery Module, 36V/60A, 2U Rack/Tower Extended Runtime External Battery Module Fast Charge Technology with Built in Battery Charger Expandable up to 10 battery modules. Output: 36 Volts /60 Amp 2U Rack/Tower Convertible Form Factor - Compatibility: OL1000RTXL2U, OL1500RTXL2U This item is Non- Returnable.3 - Year Limited Warranty