This has 1800 LEDs very close together. It has a 5-year warranty. 5400 joules in 5 minutes (3 joules /cm2). This has only the deep red 660nm which is the most studied wavelength. Not the 630 that most people have which is much cheaper. This has the most concentration of any LED I have reviewed. This sells for $1800 (1 dollar per diode). The other (pro) model with its inflated prices is at 6 dollars per diode. There is nearly a 9 times markup in the brand I used to promote. The new POLY Pro as 1820 diodes and costs nearly 7500 dollars. The market has crashed for LED prices since the prices have come down nearly to 20% of the cost since marijuana growers have bought these diodes by the millions. This is why all the prices in 2019 are finally getting lower while some companies have not lowered their prices yet.