<b>VIVOSUN: The #1 Choice for Indoor Grow </b> <br> <br> VIVOSUN focuses on designing and manufacturing quality grow lamps that <br> produce supplemental or artificial light for indoor plant growth. <br> The most reliable grow lamp on the market - 1 million+ happy users and counting <br> <br> <br> <b>Tips: </b> <br> <br> Please be aware that grow light bulb is a consumable product. Regardless of HPS, MH, LED, <br>Fluorescent or the incandescent light bulb, the fact that the total lumen (brightness) will <br>decrease in time. For an optimized growing condition, it is strongly recommended to <br> change your grow light bulb after 12 months of continuous use. <br> <b>Note: </b> <br> The trigger voltage of our ballast is 7000V, and output frequency is 100K.<br> If your ballast cannot reach the standard, then our bulb cannot be lighted up.<br>