Welcome to our store！</br>1、Wide Application: Two doorbell transmitters and two receivers, widely used in homes, apartments, offices, schools, hospitals, , etc. 2、Self Generating: When the finger presses the doorbell, the kinetic energy is converted into electrical energy, and there is no need to change the battery for the doorbell. 3、Strong Signal Penetration: Using 433.92MHz wireless signal, it can penetrate 3‑4 doors, and the receiving distance in open areas can reach 150 meters. 4、Adjustable Melodies and Volume: 38 ringtones can be switched freely, 3 levels volume can be adjusted, and silent mode can also be set to meet the needs of different scenarios. 5、Multipurpose: Not only a doorbell, but also a siren, suitable for elderly people, babies, pregnant women and patients who sleep alone to deal with emergencies. 6、Easy Installation: IP44 waterproof level, it is not afraid of wind and rain even outdoors. Complimentary double sided tape, no wiring and no damage to the wall; it can also be installed with screws. <p class="wang-edit-text"><p class="wang-edit-text"> <p class="wang-edit-text"> Item Type: Wireless doorbell Material: ABS Working Voltage: AC 100V-230V 50/60Hz Operating Frequency: 433.92MHz Standby Power Consumption: 0.25W Music: 38 Volume: 3 levels and mute Controllable Volume: ≥50dB/1m Receiving Distance: ≥150 meters (unobstructed in open space) Receiver Working Temperature: -10℃-+45℃ Transmitter Operating Temperature: -20℃-+60℃ Receiver Size: 78 x 54 x 20mm/ 3.07 x 2.13 x 0.79in Transmitter Size: 66 x 40 x 20mm/ 2.6 x 1.58 x 0.79in The transmitter does not need a battery, it is self generated by pressing <style> .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }</style> 2 x Doorbell 2 x Receiver 2 x Sticker Satisfaction - Our customers are our top priority. If you find any product problems after receiving the goods, such as damage and incorrect quantity of goods, please contact the seller immediately. We try our best to provide you with satisfactoryaftersalesservice</br>