Item Type:Wireless Doorbell Material: ABS Transmitting and Receiving Frequency: 433.92MHz Ambient Temperature:Receiver: -10℃ to +60℃ Infrared Detector: 10℃ to +33℃ Working Environment Humidity: <80% Storage Temperature: -20℃ to +70℃ Receiver Battery:3 x AA Batteries (not included) Infrared Curtain Battery:3 x AAA Batteries (not included) 1、5 Functions: The wireless doorbell has five function reminders, such as welcome, doorbell, alarm, colorful lights, and night light 2、Humanized Design: The commercial door bell has colorful LED lights, with regulable brightness, regulable volume, battery replacement memory and other humanized design 3、Long Distance Transmission: The infrared doorbell can transmit long distance, up to 280 meters in open spaces, suitable for larger places and higher floors 4、40mm Speaker: The motion sensor doorbell adopts independent alarm 40mm speaker, 8 chord music chip, the maximum is 113dB 5、Sensing Angle: The infrared doorbell senses 100 degrees horizontally, 15 degrees vertically, 2 to 8meters sensing distance (related to ambient temperature) 6、Scope of Application: The infrared doorbell is suitable for various shops, clubs, hotels, offices, factories, homes, villas, etc