b' Note: This item comes with US plug, please confirm the voltage of your area before purchasing. This item is a portable and practical wireless doorbell. 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 won& 39;t miss a visitor& 39;s arrival. Features - Color:White. - Material:ABS, electronics. - Size: About8.20X8.20X5.50cm/3.22X3.22X2.16in. - Voltage of Plug-in Receiver: 110-260V. - Consumed power: 0.2W. - Battery of Transmitter: 1 x 12V 23A Alkaline Battery (Built-in). - Ringtone: 55 Melodies (Optional). - Wireless Distance: 300M in open air. - Sound Volume: 5 Levels, 25-100db. - Silent Mode: Support. - Transmitter Waterproof Level: IP55. - Working Frequency: 433.92MHz?80KHz. - Working Temperature: -30~+70. -US: 110V. -55 ring music, adjustable volume level 5 0-100 decibels. Easy to Install, no wiring required. -Suitable for home, office, hotel, building, dormitory, factory, construction site, villa or any space that needs such service. -Efficient, waterproof and durable for a long time, it will be your good choice for wireless doorbells. '