What is the difference between 4300K, 5000K, 6000K bulbs?

4300K is a slightly off white (the brightest available), 5000K is a pure white, and 6000K has a slight tinge of blue. All OEM applications use 4300K bulbs. As you move up the Kelvin scale, your lumen rating will drop a bit, this is why we do not recommend bulbs over 6000K.