Variable light, color temperature can be changed; When the power switch in 20 seconds, each time switch on / off, color temperature will change. The first switch for the cool white 15W (color 6000~6500k), second switch for warm light (color 2700~3200k), third switch for neutral white light (color 4000~4500K). The default is a cool white light lamp, if you want to change the color, power switch can not be longer than 20 seconds, or it will restore to default light. If many lights installed at the same time, the light color temperature is not uniform, please cut off the power supply for 30s and re-power on, all lights will default to cool white.