??Rotating the knob for brightness adjustment.<br>Knob Single LED lights with Light Modulator is new and never used. With a long lifespan. Very low heat generating， besidessaving light power. No IR or UV light radiation.                                    Features            Low power comsumption and energy-saving<br>Low voltage， no flicker， no glare<br>No pollution， no UV， infrared and thermal radiation<br>It has a long using time<br>Can reduce the times and cost of replacement lamps<br>Easy to install<br>                                                                                                Package Includes            1 x Knob Single LED lights with Light Modulator<br>