Features:
New creative design: battery-free wireless doorbell.
Do not need any battery or power line to charge the transmitter， and it can transform its own mechanical energy to electrical energy by pressing the button on it.
Do not need any wire for installation， easy and convenient to use.
Transmitter can be used in both high-temperature and low-temperature environment: from -40 to 60 Celsius degree.
Transmitter is made of ASA plastic， durable to use.
Waterproof transmitter: can stand against heavy rain.
Receiver is made of ABS plastic， inflaming retarding and environmental protection.
Long wireless transmission distance: up to 160 meters (no obstacles， in open field).
Easy operation: the transmitter can be fixed on the wall by screws or adhesive pad and the receiver can be inserted to the power socket.
25 different polyphony ring tones for your choice.
Low crosstalk rate.
Blue LED light indication.
One receiver can be matched with three transmitters at the most; one transmitter can be paired with several receivers and the number of receivers is not limited.

Note: This product includes one transmitter and one receiver.

Specifications:
Certificate: CE
Color: white
Material: ASA & ABS plastic
Power supply: receiver: AC100-240V， 50~60Hz; transmitter: self-powered
Ideal transmission distance (open field): 160m
Radio frequency: 433MHz
Sound level: 85dB (at 1m/ 3ft)
Power consumption: ＜200mw
Transmitter operating temperature: -40 to 60 Celsius degree
Receiver operating temperature: -10 to 40 Celsius degree
Transmitter size: 8.7 * 4.5 * 3cm/ 3.4 * 1.7 * 1.2in
Transmitter weight: 75g/ 2.6oz
Receiver size: 8.5 * 7.7 * 2.7cm/ 3.3 * 3.0 * 1.0in
Receiver weight: 86g/ 3oz
Package size: 20 * 18 * 7.7cm/ 7.8 * 7.0 * 3.0in
Package weight: 222g/ 7.8oz

Packing list:
1 * Transmitter
1 * Receiver
2 * Screws
1 * Adhesive pad
1 * User manual