Sunmaster 600W Watt Hps Dual Spectrum Grow Light Bulb Lamp Hydroponics Sunmaster HPS Lamps are High Pressure Sodium lamps designed to deliver 10% more light than standard HPS lamps. This extremely energy-efficient plant grow lamp provides more energy which is essential for optimized photosynthetic response. Long life, economical and electronic ballast friendly Ideal companion for Metal Halide Conversion Lamps Red output for stem elongation and flowering 10% more light than a standard HPS lamp