https://www.lightsourcecentral.com/product-page/ge-mvr400u-400w-ed37-mogul-e39-universal-metal-halide-bulb
GE MVR400/U 400W ED37 Mogul E39 Universal Metal Halide Bulb | Lightsourcecentral
The GE MVR400/U 400W E39 Metal Halide Bulb, offerS 36,000 lumens and 20,000 hours of life. Perfect for universal burn positions!
https://normanlamps.com/h33gl-400-dx-400w-mercury-vapor-coated.html
H33GL-400/DX - 400 watt, ED37, Coated, E39 Mogul Screw Base
H33GL-400/DX - 400W, Mercury Vapor, Coated (H33GL400/DX) - 400W, E39 (mogul screw base), 23,000 lumens by Sylvania | Shop at Norman Lamps
dxwattcoatedmogulscrew