Yale Receiver Module - to Pair with Remote Control & Video Door PhoneYale YRM 20N is a Receiver Module to integrate Yale Smart Lock with various type of devices It is inserted inside behind the slot available inside the battery cover of the lock YRM 20 N acts as receiver module while integrating with devices like Yale Remote Control or any Video Door Phone YRM 20 N is compatible with following Smart Door Locks: YDM 3109, YMF 40, YDD 424 , YDR 41, J 20, YDR 4110, YDM 7116, YDR 50G, YMI 70, YDM 4109 Works with Video Door