A quality low-profile troffer with specification features for NEMA “G” grid, NEMA “NFG” narrow face grid, NEMA “GR” grid regressed, NEMA “NFSG” narrow faced slot grid, or NEMA “F” flange ceiling types. 3” nominal housing depth, 3-3/16” maximum depth. Smooth rolled edges on all four sides for easy handling. Die-formed one piece housing includes stiffening embosses and provides increased rigidity. Housing is multi-stage phosphate treated for maximum corrosion resistance and finish coat is high reflectance baked white enamel. Lamp pin openings in housing ends for easier relamping (can be relamped without using openings). Integral baffling system to prevent light leaks. Self-contained fluorescent emergency power packs can be incorporated, listed for dry locations. Rotating ring locking lamp holder is standard for secure and positive retention of lamps.