The KooPower Wireless Doorbell makes installing a doorbell in any home or building quick and simple with absolutely no wiring required! The KooPower Wireless Doorbell is a state-of-the-art alternative to conventional wired doorbells. - Its IP44 waterproof rating makes it suitable for use indoors or outdoors. - Before mounting 2 Receivers and Transmitter into walls, please pair them according to the manual, and do some tests. - Then, plug the receivers in up to 150 meters away in the open air. The range will be influenced depending on operating circumstances. - Follow the setup instructions provided, and you'll be able to use your doorbell right away. We give you all of the hardware needed for installation! With the KooPower Wireless Doorbell, you're in full control of your doorbell's sound and volume. There are 25 different musical chimes to choose from, and selecting the sound is so easy, you can pick a different one every day! The doorbell also features an adjustable volume with three levels from 50 to 80 decibels to suit your needs. By the way, if you have a couple of these units it is also possible to pair them, so you can have a bell push at both the front and back door and have two or more bell sounders which stay in sync with the melodies but slightly out with the timing which creates an interesting effect. Unlike other wireless doorbell sets that detract from the appearance of homes and businesses, the KooPower Wireless Doorbell adds a sleek finishing touch to your decor. Its clean, modern look and white color allow it to look at home in any setting. Our wireless doorbell also eliminates the hassles of having to change batteries or recharge your receivers, making it the most convenient way to add a doorbell to any building.