I would give this LED light a B+ because there is one white light on each of the spheres that is burnt out and notfunctioning properly. I would give this light an A+ otherwise, if they were all working. However this defect did not affect the productivity of the plants, and the light was very intense and bright. The plants all blew up like monsters, and I was very satisfied with theamazing end results. Also, I had a much lower electric bill, than when I wasusing HPS lights. And, the nutrients I bought from Grow-ace are the best in the business.GROWACE RESPONSE: Thank you for your honest review of the product. All of the Advance Spectum Max S Series lights come with a UV spectrum built into each of the diode clusters. This UV spectrum diode is placed specifically for medical plants to promote resin growth during the final stages of growth. UV spectrum wavelength is not visible to the human eye due to where it lies in the spectrum map, however rest assure that it is highly visible to plants!