HID HUT, Inc.’s 400W MH bulb is an awesome deal!!! It has a nearly identical color spectrum (if not better) than the most popular Horticultural bulb on the market- for a fraction of the cost. It has 43791 lumens of output, with a color temperature of 4165 kelvin, and a color rendering index of 65. It has an average bulb life of 10,000 hours and can be used in vertical or horizontal orientation. Check out the spectrum charts from actual testing! Ours produced over 43000 lumens, the Hortilux produced 26,130 lumens- big difference. We promise you will be satisfied!!!