This HID tubular pulse start metal halide light bulb offers an incredibly bright white light that can be used in closed luminaires in large commercial and industrial spaces.It is ideal for use in commercial floodlights. Fitted with a GES-E40 Goliath Edison screw (40mm) cap (sometimes known as a giant screw cap).The 400W light bulb emits an outstanding 40000 lumens of cool white 4200K light. Its long 20,000-hour life rivals many equivalent LED floodlights. The light bulb has an E40 giant Edison screw (GES) cap and Horizontal +/- 75, so is compatible with many standard fittings.NB. operates from Metal Halide control gear only.75 operating position. For use in closed luminaries. Non-dimmable.