NT1-296 Rack
Up to 16 NT1U-223TC cards can be installed in this rack, supporting up to 96 ISDN terminals.

NT1-200/296 Battery Backup, NT1-200 Add-on Battery
Battery Backup allows the NT1-296 Rack and terminals to operate during a power failure. Battery capacity may be doubled with an additional NT1-200 Add-on Battery.