Wired Intercom Doorbell Phone with Door Unlock Function

Visitor presses the button on the door unit, the room unit rings. Host picks the handset up and talks with visitor. Upon confirming visitor identity, just press the door release button on room unit to open door. Please be noted that the unlock button on the room unit works on the door lock that you have is the electric one. The door unit and room unit are connected by two wires.
Features
Two wires connection between door unit & room unit.
Door release button on the room unit. This function only works on the electric door lock. And the system uses two wires from room unit to electric lock.
A plug - in room unit connects with 220V power, designed for desk use or wall mounting.
The door unit can be put into any standard door outlet.
Long operating distance, loud and clear sound.
200M RVV 4 x 1.0mm wire is recommended to use.
Specifications
Power AC 220V
Mounting Type Surface Mounted Type
Effective Wiring Range 200M
Wiring 2 wires from room unit to door unit, 2 wires from room unit to electric lock
Door Unit Dimension 10.5L x 8W x 3.5H cm
Room Unit Dimension 22.5L x 9W x 4.5H cm
N.W. 750g
Package Size 32L x 22W x 8H cm