Specifications:Receiver:Working voltage: 200-240VWorking current: ¡Ü120mAPower: 2WPower charger: EU plugMusic: 36 cord music for optionSound: 25-80dB (4 grade volumes)Remote control distance: 100m (in open air)Work frequency: 315MHzTransmitter:Work voltage: 12V (Battery Model: 23A 12V、 not included)Work current: ¡Ü15mA(20 times a day by calculating、 a high quality)LED indicator: press the send button、 LED indicator light will flash、 emitter work and the receiver receive the order and then send out the beautiful music reminded you the VIP visit、 the blue-ray LED of the receiver will regular flash along with the musicTemperature: -10 -50 'cProduct dimensions:Receiver: 9.5 * 6.0 * 3.4cmTransmitter: 8.4 * 6 * 2.3cmProduct weight:Receiver: 72gTransmitter: 37gPackage List:1 * Wireless Electronic Doorbell Receiver1 * Transmitter2 * screws1 * User Manual(English)