Fully assembled housing is formed and welded, 20 ga. steel, chemically treated to resist corrosion and enhance paint adhesion. Standard finish is high reflectance white powder coat, applied post production. Rotational locking lamp holders. Included end feed connector (installed by others) accepts 3/8 in. steel flex conduit (available seperately). Available for T5 14W, 21W, 28W, 35W and high output 24W, 39W or 54W linear fluorescent lamps. Available lamp overlaps of 6 in. Standard 120V or 277V electronic high power factor ballast is pre-wired to the lamp holders. UL and ULC listed for dry and damp locations.