Ge, mvr400/u/cp, 400w, clear multi-vapor metal halide lamp, ed37 bulb shape, universal burn position, mogul base, mol=11.5, 20,000 hour, 36000 lumens, 4000 kelvin color temperature, cri=65, m59 ansi ballast type, 90% @ 50% of life lumen maintenance, universal burn position, for open or enclosed fixtures.