GE Lighting 400 Watts Metal Halide HID Lamp, ED37, Mogul Screw (EX39), 42,000 Lumens, 4000K Bulb Color Temp.

These HID and LED HID-replacement light bulbs have an extended mogul screw base, also called an EX39 base. The EX39 base has a longer center terminal than an E39 base and can be screwed into both E39 sockets, which are typically found on enclosed fixtures, or protected EX39 sockets, which typically found on open fixtures. The base has a 39mm diameter. EX39 medium screw-base HID and LED HID-replacement bulbs produce a lot of light and are commonly installed in fixtures with a high mounting height, such as street lights, floodlights, and high-bay and low-bay lights in warehouses and convention centers.