Sunmaster HPS lamps are a very popular choice amongst growers and come at a great price. The 600w Sunmaster Dual Spec HPS Lamp has a lumen output of 90000 the majority of which is in the orange/red part of the spectrum, they also produce more blue than most other dual spectrum lamps making them ideal for vegetative growth and flowering.The Sunmaster range of lamps has proven to be excellent value for money providing reliability and quality lamps time and time again. Horticultural lamp light output will decrease with use.We recommend that growers replace lamps at regular intervals to maintain optimum yields at least every 6 months Impressive 90000 lumen output Dual Spectrum lamp for use in vegetative and flowering stages. For maximum efficiency and performance replace lamps after 6 months of use