Hotel Multi Guest Room Commercial Wireless Digital Ding Dong Doorbell

You can combine push buttons and receivers by yourself. This wireless doorbell has built in temperature probe. It can display temperature in real time. Press doorbell button, doobell will ring, LED flashing at the same time.

Product List: 1 receiver, 1 transmitter, 2 screws, 1 double-sided adhesive sticker, 1 battery.

 AC type, plug-in receiver 

 Built in temperature probe, temperature display in real time
 IP44 Waterproof transmitter, battery powered
 51 polyphony melodies
 4 levels of volume adjustable (mute included)
 Up to 120 meters operation range (open area)
 Easy to install and use
 Learning code function
 Low power consumption

For AC receiver: Just plug receiver into standard outlet in the room, then it will work. You can choose melody you want.
For Transmitter: 2 methods. Please first test whether the operating range you choose is working or not. 
Method 1:
Use double-side adhesive sticker to fix transmitter on the wall. 
Method 2:
Please prepare electric drill, screwdriver.
1. Find the hole on transmitter back cover, use slotted screwdriver to push into the hole.
2. Make marks of location on wall.
3. Make holes in the wall with electric drill. Then insert back cover with screws(provided in the package).
4. Finally, put back front case with PCB board.

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