Sunmaster BulbsThis Sunmaster 600W dual spectrum HPS grow lamp puts out both red spectrum and enough blue spectrum light to be used as a sole light source throughout all stages of growing. This eliminates the need to buy separate metal halide and HPS bulbs for the vegetative and flowering fruiting stages of plant growth. Dual spectrum lamps are increasingly becoming a number one choice for growers as more and more are discovering these bulbs do a great job