Introducing the Phantom PHE400 digital grow light ballast! Drive any 400-watt metal halide or high pressure sodium bulb with ease. This digital ballast features a tri-mode micro-processor for energy savings and contains hot restrike technology, which senses high lamp temperatures, and will not ignite until a safe operating temperature is reached. Not only is the Phantom PHE400 the most rigorously tested ballast on the market, it also drives the highest light output for maximum plant growth. On top of the energy savings, this ballast runs completely silent and it is the only ballast on the market designed for vertical operation, allowing for cooler operation and optimum grow space. Includes a universal reflector adapter and 8-foot, 120-volt heavy duty power cord. 240-volt cord sold separately.