Horti King dual spectrum bulb The Horti King 600w duel spectrum HPS Bulb Produces a spectrum of light that is suitable for your plants in both the growing and flowering stages of its life. Producing 90000 lumins of light with a 2000K colour temperature. Duel spectrum lights have more blue in the spectrum than traditional red spectrum HPS bulbs and this helps the formation of more compact plants with shorter internode distances. The bulb is priced to enable it to be sold with budget light kits while still producing good overall results for the hobby grower.