This 600 watt Metal Halide conversion lamp will work in any standard 600 Watt High Pressure Sodium fixture. Gavita makes the perfect horticultural optical system. They engineered the reflector optics and built them into the lamp. Then they perfectly aligned the arc-tube to maximize lumen output at an astounding 95% efficiency. Because the reflector is on the inside of the glass, there is no need for assembly, and the reflective material never needs cleaning. Works with any standard 600 Watt High Pressure Sodium ballast. Produces 55,000 Lumens.