Welcome, AJLIFTED.
QB's offer a simple way to use state of the art diodes in your build. For that area(4x4), I would plan on running 30w/sq ft to get a decent light level so 480w for you 4x4 should do fine. HLG's website and ledgardener.com is also a great resource to help design and chose the appropriate components. Spend a little time researching what would be the best choice for your grow space and build from there. Have fun and be prepared to grow some serious dank with that fixture.