The answer is yes. Set up your socket with the first remote controller in the normal way, then do the following:
1. Turn off the socket.
2. Press and HOLD down the button on the socket for 5 seconds.
3. Release the button, the light will flash slowly.
4. Press the on or off button on the channel you wish to use on the second remote controller, the light will flash quickly.
5. The socket will now operate from both remote controller units on the channels you selected.