7 FLASHING COLORS: Features 7 vibrant flashing colors that can be adjusted to your preference, adding a decorative touch to your doorbell. MUSIC SELECTION: Choose from multiple built-in musical options to create a welcoming atmosphere in your home. WIRELESS DESIGN: Enjoy a hassle-free setup with the wireless design, offering convenience and quick installation without complicated wiring. SUITABLE FOR ELDERLY & HEARING IMPAIRED: The loud volume and flashing lights ensure that the elderly and hearing impaired can easily notice the doorbell. PRACTICALITY: In addition to being a doorbell, it can also be used as a pager for young and old with special needs, allowing them to call family members or caregivers with the push of a button. Dry batteries not included. Working Voltage: DC4.5V (3 batteries) Working Current: less than 200mA Encoding Method: power. Music: 16 songs Volume: 0dB~85dB (3 levels adjustable) Receiving Distance: more than 100M Size: Transmitter: 8*5*2.2cm/Receiver: 10.2*6.7*3.0cm