The SMX48RMBP2U is an external battery pack for APC Smart-UPS X, a line of uninterruptible power supplies that provide network power protection and extended runtime for servers, routers, switches, and other devices. It has a voltage of 48V, a capacity of 864VAh, and a rack-mountable form factor of 2U. It can be connected to an existing APC Smart-UPS X to increase the battery runtime during a power outage. It also has hot-swappable batteries, intelligent battery management, and a 2-year warranty.