Self-powered wireless doorbell: no battery, no wiring; no batteries; easy to install, and very environmentally friendly. Long Range: Maximum range of 200 meters in the open area without obstacles, the effective distance at 3 volume levels allows you to hear the ringtone and respond to the door in time. The wireless, battery-free doorbell has 38 different chimes and 3 adjustable levels to suit your needs. Easy to install and use: The transmitter can be used with 2 types of installation. Use the included tape or screw to secure the transmitter to the door frame. And the doorbell receiver in the socket to start. 38 sounds to choose from The wireless doorbell without battery offers 38 different ringtones with 3 adjustable sound volume levels to choose from. Easy Setup Self-powered doorbell, without any batteries, just plug the receiver into an electrical outlet. The push-button transmitter can be attached to the edge of the door using the screws or adhesive tapes provided. Multiple use Suitable for home use, apartment, office, villas and more. Elderly or disabled people can also use it as pagers! Make sure you don't miss any visitors, you can hear the sound evenfrom the back of your garden.