Wireless doorbell set: the wireless bell system consists of 1 plug-in receiver and 1 portable transmitter. It works out of the box and is fully coupled. Suitable for all types of houses, apartments, gardens, garages, mailboxes, offices, schools, nursing homes etc. 400 m wireless range (open area). The doorbell set has a built-in high-quality transmitter chip. Ring in real time when someone presses it, which confirms that you do not miss any visitors or deliveries. Strong penetration. Stable signal penetration through walls and doors without disturbing electronic devices in the house. Expandable function. If you want to increase the radio coverage in your home, you can add multiple receivers or buttons to pair your existing doorbell 0 dB mute and LED flash. The LED flashes as open. When there is one and presses on the house doorbell and is very friendly to the hearing impaired. If you do not want to be disturbed, you can set the mute switch to 0, but the LED still flashes to display. Memory function. Remembers previously set music and volume levels, you do not need to repeat the settings even after a power failure. You have the choice between two installation methods. 1. Attach the button to the wall or door frame with the included double-sided tape. 7. Attach it with screws (included), but for this you need a small electric drill to drill holes in the wall. Note: Do not attach the doorbell to a metal surface as this shortens the wireless range. Other uses of the doorbell You can use it as a pager if there are people in need of care at home, such as pregnant women, the elderly, people with mobility restrictions who can be helped by pressing the button.