The Ultra Sun 901534 400 watt metal halide grow lamp is designed to rival bulbs three times the price. Its digital technology is engineered to operate with modern horticulture equipment and maximize output and longevity. A ceramic insulation plate, a stainless steel armature, and a newly designed proprietary starter allow this lamp to withstand the acoustic resonance and harmonic distortion of high frequency electronic ballasts. At 7500K, this HID lamp creates 32,000 lumens of light within the blue spectrum, making it perfect for the vegetative growth stage of your plants. Its 15,000-hour life is backed by 1-year warranty, so try it for yourself!