: Home Security Smart Door Alarm LED Light 38 . Product Description: Just press the button, doorbell will receive the signal and you will hear the tunes immediately. remind you of the arrival of visitors. 5 adjustable volume level: different sound sizes in different situations. Strong signal: Long operating range can be up to 100m in open space, perfect for home including villas, apartment, offices, , warehouses, etc. Easy to install: Just plug the receiver into power socket and attach the transmitter on door, you 't even necessarily have to make holes or damage anything. Item Type: Wireless Frequency: 433MHz Operating Voltage (For ): AC220V Battery (Wireless Button): 3V CR2032 (Battery Not include) Plug Type :EU Plug,it applies to Indonesia, , , , and so on. Colour:black Material:ABS Package Contents: 1 x 2 x button (3V CR2032 battery not include) Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.