This battery pack option allows the addition of four battery units to be coupled with either the 7500-volt or 10, 000-volt Uninterrupted Power Supply (UPS) to provide extra runtime to the rack in the case of a power failure. Up to four of these Extended Run Battery Packs can be used with one UPS. This cost-effective, battery-pack option helps protect and extend the backup power runtimes of mission-critical, high power-density applications.