Features: The receiver can remember your set ringtone, is waterproof and has a USB power supply! How to use: Press and hold the volume button on the receiver for about 5 seconds until the light turns on - release the volume button, then press the button immediately to pair the doorbell and receiver successfully. Colour options: Choose from either black or white. Doorbell: Grab yourself a wireless smart doorbell. Variety: Choose from 60 different doorbell tones! Volume levels: Can be set to 5 different levels of volume as well as mute. Wireless Smart Doorbell | Black | Living Social