Retevis Wireless business Calling Device, with the Duplex mode like the phone, It help you to build the intercom system. Perfect for family and office. Remember the model RT57 What are the different from the other brand? Duplex work mode Yes, our RT57 with the duplex work mode, you can talk to another users if they are speaking at the same time. But in the market, there are lots of devices similar with us but with the simplex mode. You can not talk to others if they are speaking. How to use this Wireless device RT57? 1, Set Number of your own RT57 Press Call button to connect it to the power, When numbers flashes in the display, press <▲> or <▼> to select …
