BP72V18-2US rack/tower external battery pack offers extended battery runtime when used in conjunction with expandable 72V rack-mount or 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 72V external battery packs to the host UPS. Included mounting accessories support 2U rack-mount installation in 4-post racks. Options for 2-point front-rail mounting, 2-post center-mounting, wall-mount and upright tower installation available.Compatible with these UPS systems: SU3000RTXL2U, SU3000RTXL3U, SU3000RTXLCD3U, SU3000RTXR3U, SU3000RTXR3UHW, SU3000XL, SUINT3000RTXL2U, SUINT3000RTXL3U and other UPS systems that specify the use of this battery pack.