Main features: | U-shaped metal bar diameter 8 mm Work load 350 kg Corrosion resistance | Wiring - 2 wires without polarity, Relay output : 1 pcs or 2 pcs - B5 Module, Support up to 4 door stations, Intercom function, Number of ring-tones : 12, DIP SWITCH for configuration and addressing, Connector for an additional bell button |