This is one bright light! It’s got blue and red light components as well as full spectrum white and well suited for any grows throughout the plant process. The entire back of the light is sold metal and acts like a huge heat sink.even the power supply is raised off of the back to allow heat to dissipate from the power pack. This is a large unit - for me it takes up much of my grow tent area.
Just for reference, I tested this light with an electric watt meter. At 25% it starts out just under 100 watts. At each step up, it adds another almost 100 watts until full power, it’s at 391 watts so essentially it is at what they advertise at.
Compared to the 400w HPS lighting, this is light years brighter (pun intended!)