Proper lighting is a key ingredient in promoting robust, healthy growth as well as meeting the needs of various plant growth phases through optimized spectral outputs. Sunmaster� provides the largest, most comprehensive supply of HID lamps specifically tailored for the hydroponic and horticultural industries. Simply stated, Sunmaster� lamps deliver intense light output with nutritional spectral values. Metal Halide Conversion Lamps are designed to be used in High Pressure Sodium Ballasts.