The MFS 1 set is ideally suited, for example, as a replacement for defective garage door radio controls for controlling an existing garage door control (with existing button input and protective circuit). If the garage door control has two separate control inputs for UP and DOWN, an FE3 D2 with two switching outputs is preferred to the FE3 SE.

Any other radio control application can also be implemented quickly and easily using the potential-free changeover contact on the receiver.
 
Additional hand transmitters (of course also receivers) can be integrated without problems (advantage: further radio transmitters can be added very simply by setting only the same DIP switch address here - thus flexible and easily expandable, e.g. for garage entrances, etc.).