Product information:
-Colour: Black
-Material: Plastic
-Size Receiver: Approx. 8.1 x 8.1 x 2.5cm
-Size Transmitter: Approx. 3.4 x 2 x 7.5cm
-Voltage of Plug-in Receiver: 110 to 260V, 50 to 60Hz
-Battery of Transmitter: 1 x 12V 23A Alkaline Battery Built-in
-Battery of receiver: AU PLUG Power Supply
-Ringtone: 55 Melodies Optional
-Wireless Distance: 300M in Open air
-Sound Volume: 5 Levels, 25 to 100dB
-Silent Mode: Support
-Transmitter Waterproof Level: IP55
-Working Frequency: 433.92MHz more or less 280KHz
-Working Temperature: -30 degrees C to 70 degrees C

Contents in Box:
-1 x Wireless Doorbell
-2 x Receivers

More information about product:
-Remote range of 300 meters in open air, which makes it easier to hear the doorbell wherever you are in your home, you can take the transmitter throughout your home and will not miss a visitors arrival.
-Expandable and DIY pairing. You can DIY by pairing additional receivers and push buttons to meet your requirement. Each push button transmitter can pair one or multiple receivers. -Multi-functional. There are 55 Chime tones with 5 levels volume adjustment for options to delivers rich and crisp sound.
-The push button is rated IP55 waterproof to meet the needs of different environments.
-Easy to use. Simply plug the door chime into a power supply. No any wire or battery required.
-If a visitor enters, the LED of the receiver will regular flashes along with the music. LED light will flash according to the rhythm of music.
-Great for commercial places, factories, hotels and offices, also work well for large homes or villas, etc.
-Energy saving and eco-friendly design, the push button transmitter can last for 25 year 5 presses per day.