Feature: 1. 38 MUSIC AND 4 VOLUME LEVEL: The wireless doorbell offers 38 music choices including voice ringtones from around the world, one touch music switching, 4 levels of volume adjustment, including mute flash. 2. TIME, TEMPERATURE AND HUMIDITY DISPLAY: Wireless doorbell has Fahrenheit and Celsius settings available for control to measure the temperature in the space in real time. Switch display unit with one click. 3. HIGH DEFINITION DIGITAL DISPLAY: The receiver is designed with a digital display, strong light based PC board display, clear display, easy to read, improve the visual enjoyment of reading. 4. EASY SETUP: Ready to use out of the box, wireless transmission, plug and play. Plug the mini doorbell receiver into an outlet. Secure the button to the wall with double sided tape. 5. LONG RANGE: This high frequency electronic wireless remote doorbell adopts FM signal programme, anti interference, easy to penetrate the wall, range up to 100M. Specification: Item Type: Self Powered Wireless Doorbell Material: ABSColor: Black and Gold Receiver Input Voltage: 85-260V AC Transmitter Power Supply: Self generating (Pressing a button converts kinetic energy into electricity; No battery, can produce automatic power supply) Waterproof Level: IP44 Operating Temperature: 0°C-99°C Operating Humidity: 0%-99% Operating Frequency: 433.92MHZ Melodies: 38 Volume: 4 levels Temperature Display: Adjustable between Celsius and Fahrenheit Time Display: 00:00. Package List: 1 x Transmitter 1 x Receiver 1 x User Manual