General Electric HR400A33 Mercury Vapor Lamp Bulb

General Electric HR400A33 Mercury Vapor Lamp Bulb is a 400-watt mercury vapor light source built for installations that use a mogul screw base. The bulb features a large E39 mogul base, allowing it to fit fixtures designed to accept mogul sockets. The HR400A33 designation identifies this specific GE lamp model, ensuring correct wattage and base for mercury vapor HID systems that rely on an appropriate ballast. Mercury vapor lamps like this are high-intensity discharge lamps that require a ballast to regulate current and voltage and are known for broad-area illumination. This GE lamp is manufactured to GE's specifications for reliability within the mercury vapor family, and the HR400A33 part number helps ensure you select the correct replacement for fixtures designed for 400-watt mercury vapor operation. The combination of 400 watts, mercury vapor technology, and a mogul E39 base defines its role in replacement scenarios where a like-for-like GE bulb is required.