BP36V42-3U rack/tower external battery pack offers extended battery runtime when used in conjunction with expandable 36V rack-mount and tower UPS systems. Includes heavy-gauge cabling with high-current DC connector for safe, simple installation. Included daisy-chain connector enables the connection of additional compatible 36V external battery packs to the host UPS. Included mounting accessories support 3U rack-mount installation in 4-post racks. Options for 2-post center-mounting and upright tower installation available.Compatible with SMART1000RMXL2U, SMART1200XLHG, SMART1500RMXL2UA, SMART1500RMXLN, SMART1500XL, SMX1200XLHG, SMX1500XLRT2U and other UPS systems that specify the use of this battery pack.