Wireless Doorbell Communication Wireless Digital Music Doorbell Home Sensor Remote Control Caller Features: Use the built-in battery to power on, press your finger to turn on the power. It can be wirelessly connected, with four adjustable gears and adjustable strength as needed. LED flashing reminder with strong penetration. This is not a doorbell, but also a pager: elderly people, children, and pregnant women all have needs, so when do you ring the doorbell to sleep at night. 200 meters and strong penetration: Strong penetration performance, with a receiving distance between 200 meters and the ground. It can mute with one click to avoid interference. There are 52 options for music ringtones: the door ringtone is not a "ding dong" sound, but can also achieve free switching of 52 chords, with melodious sound quality. Press the doorbell button and the receiver will sound and flash. Digital circuit design, multiple sets of use, no serial port noise, can effectively avoid the trouble caused by interference between neighbors. Product Description: Material: ABS Receiver: 10.3 * 6.1 * 2.5cm Emitter:4.5 * 1.8 * 2cm Receiving distance: 200 meters Volume adjustment: 4th gear Internal ringtones: 52 types Transmitter battery: 12V/23A Frequency: 433mhz+0.5mhz Receiver: plug in the power supply for use (85-265V) Product contain:1x button, 1x bell, 1x double-sided adhesive, 1x manual