A. Features 300m/1000ft range and 85dB max sound intensity, this wireless doorbell comes with 2 transmitters linked to 2 receivers. Individual pairing ensures that each button has its own ringtone to know which door someone is at. B. Equipped with a speakerphone and a chip for stable music, it has built-in 36 melodies, producing clear sound. There are four adjustable volume levels from 25dB to 85dB, allowing you to hear it easily around the house when the bell rings. A memory function is available for sound and chime selection. C. Made of superior material, the wireless doorbell has an IP44 waterproof standard for the transmitter, ensuring stable performance for outdoor use. The blue LED on the button and receiver serves as a visual indication for guests and visitors, and is also a thoughtful design for the hearing impaired. Visitors can know they've used the right doorbell as it lights up when pressed. D. No wiring is required. Simply plug the outdoor wireless doorbell receiver into an electrical outlet and install the push button with the included double-sided tape and screws. A template for drilling screw locations is included if you choose to drill holes to mount the push button. The wireless doorbell is easy to use. Two receivers can be placed anywhere, so you will never miss your visitor. Features: Internal sounds: 36 chimes Volume: 4 adjustable levels (25dB~85dB) Wireless range: 300M/1000 ft maximum Transmitter power: 1 x 12V 23A battery (included) Input voltage: AC110-240V 50/60HZ Waterproof (transmitter): IP44 What you can get: 2 x Transmitter, 2 x Receiver, 2 x Tape, 4 x Screw, 1 x Screwdriver.