Keep critical loads online longer when outage windows stretch beyond the base UPS runtime. The APC Smart-UPS X 120V External Battery Pack is designed for Smart-UPS X systems that need additional battery capacity without changing the core UPS platform. Its rack/tower form factor fits mixed deployment environments, from structured rack rows to standalone tower installations. For teams protecting servers, network gear, storage, and edge infrastructure, extended runtime is not a convenience feature — it is an operational control point. More battery capacity means more time to preserve transactions, maintain connectivity, and execute orderly shutdown procedures when utility power fails. It also gives facilities teams a wider margin during generator transfer or unstable power conditions. This battery pack is a practical fit for organizations that have already standardized on APC Smart-UPS X hardware and want to scale runtime in a predictable way. Rather than replacing the UPS, you extend the protection envelope with a matched external battery solution built for the platform. That makes it easier to align power protection with workload criticality, rack density, and recovery procedures.