LED Dimmer is a controller that it can adjust brightness infinitely,its control mode is knob-operated control, you could adjust light to the appropriate lighting brightness in accordance with your actual need. The LED dimmer offers LED intensity control with integrated on/off via pulse width modulation. Dimming your LEDs you can decreases energy consumption while increasing LED life and reliability. Combine 3 LED dimmers and red, green and blue LED arrays to create a manual RGB controller. The LED dimmer is for low voltage, dc devices only, not for use with low voltage ac or fluorescents.