Sonoff B1 is white and colour ambiance dimmable LED bulb with E27 screw base. The dimming led lamp can be dimmed or brighten via iOS/Android App. With the App, users can select White, then the light will become white ambiance, they can set colour temperature from cold to warm and change the brightness from 1%-100%. If they select a colour, they can change colour spectrum of the RGB bulbs to favourite atmosphere. There are four available scenes for the dimming LED bulb: rest, reading, party and casual. The Sonoff B1 E27 colour LED bulb is compatible with Amazon Alexa(Amazon Echo, Echo Dot, Tap). Users can ask Alexa to dim or brighten, or adjust the colours of the led light bulb.