The Bosch LBB 1957/00 keypad is an extension to the LBB 1956/00 Plena Voice Alarm Call Station that adds seven additional zone-select keys. The LBB1957/00 has the same stable metal base as the call station. In addition to tabletop use, the special design allows it to be neatly flush-mounted on desktops. Seven zone selection keys (6 programmable keys and all call) LED indications for zone selection Up to eight keypads can be connected together EN 60849 compliant Emergency, call, power, and fault indicators Use in conjunction with the LBB1956/00 call station