The Sylvania GROLUX bulb is the only bulb in this country that was designed from the ground up specifically for growing plants (yes, even the Hortilux bulb was not originally designed for plants!). It has the highest PAR rating (meaning it has the highest plant-usable light output) of any bulb on the market, in addition to having 30% more blue spectrum than a standard HPS bulb. It is the best bulb you will find in the U.S., far exceding the performance of all other bulbs currently available, including the Hortilux (and for less money!).

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