Separate up/down lamping and switching. Rows with continuous, uninterrupted diffusers or baffles. Precision alignment and joining system for smooth architectural appearance. P-ID-66N is a 6-inch wide T8 fixture, in 3-, 4-, 6-, and 8-foot lengths, with indirect/direct distribution. It includes separate lamp chambers and multiple lamping options for illumination control. Options include 1- and 2-lamp indirect plus 1- and 2-lamp direct combinations. Lamp chambers are wired to switch indirect and direct components separately, providing two levels of light.