Intercom uniphone for expanding sets from the FOSSA series OR-DOM-RL-901UD

Uniphone for expanding entry phone sets OR-DOM-RL-901, OR-DOM-RL-903, OR-DOM-RL-913
a small number of wires 2+2
uniphone has a built-in power supply and power cord
power supply via direct connection to 230V/50Hz
each uniphone is protected by a fuse