Correlated Color temperature (CCT) is the measure of a lights color. The CCT rating of an LED lamp indicates the relative ‘warmth’ or ‘coolness’ of the appearance of white light generated by the lamp. Color temperature is expressed in degrees Kelvin (K). Generally speaking, color temperatures 3200K and below are considered to be ‘warm’ and therefore are a slightly more yellowish white, and color temperatures above 4000K are considered ‘cool’ and therefore are a slightly more bluish white. A light source with a color between 2700K and 3000K are most appropriate for residential applications or as an incandescent or CFL replacement. A light source with a color temperature between 3200K to 3500K would be considered to be bright white and are appropriate in residential and light commercial applications such as boutique retail, classrooms and hospitality venues. A light source with a color temperature 4000K and above are ideal for any commercial application including big box retail, electronics stores, industrial and technical manufacturing where superior visibility is essential to shopping, production and security.