Upgrade your mercury and orange sodium (SON) elliptical light bulbs to bright, crisp white light with these metal halide retro-fits. Able to operate off of both mercury and SON control gear, these HID light bulbs are the easy, confusion-free way to replace your old light bulbs. Fitted with a GES-E40 Goliath Edison screw (40mm) cap (sometimes known as a giant screw cap).With a rated life of 10,000 hours, these elliptical metal halide light bulbs give less glare and are perfect for industrial applications. This light bulb contains glass with a special coating to filter out all harmful UV rays - this removes the need for the light bulb to be installed in a fitting with additional UV protection.Important information; External ignitor required. Can be operated on standard Mercury or SON control gear. This metal halide light bulb requires an enclosure with cover glass.Universal operating position.