This clever accessory plugs into the end cap of any of our ATR,SESC,SETTS range of screens and makes them ready to receive RS232 commands via Serial or you can use our software to control via any PC by using the usb connection. This also has the same functions as a standard wall switch with is up/down and stop. The small plug and the fact that it does not require mains electricity makes this useful when needing to run through small conduit already built into a wall. The cable length is approx 2.7m with an RJ12 connection that plugs directly into the left end cap on the screen. No wiring involved as it's plug and play.