The 6400-00056 is a UPS Battery Backup is maintenance-free sealed Lead-Acid battery with suspended electrolyte, leak-proof. Alarm when on battery - distinctive low battery alarm, overload continuous tone alarm. During a power outage, it's important that administrators have the ability to communicate instructions to faculty and students. A properly outfitted campus will have POE switches with UPS battery backup, POE extractors at the IP audio endpoints, and UPS battery backup at the Admin Station to allow for control and communication. This UPS Battery backup is designed to keep the Admin Station (computer and CM3000) running for at least an hour. It is included with FR-ADMIN, but if you are adding secondary admin stations using your own computer, we recommend this model.