The light aperture on these light boxes is installed directly over the lamps to diffuse and color-shirt the light, providing balanced lighting with fewer lamps. Average brightness of the viewing area on these light boxes is photo metrically checked and balanced to the value recommended by the Illuminating Engineering Society. Light aperture seals and dissipated heat build up from the work surface of these light boxes, discharging it through air flow convection ports for continuous cool operation. The Satin glow is so thin (3 inches) that no adjustment in table or drafting height is normally required to have comfort while using our light boxes.