Fixture size is approximately 80cm x 55cm.
Consists of 720 Samsung LM301B LEDs, spectrum depending on PCB stock:
Assembled, currently available:
144 * 4000K LM301B576 * 3000K LM301B
(3200K spectrum, better for flowering than vegging, but can veg too).
Slightly 'logarithmic' placement, for more even PPFD.
According to the Samsung LED Calculator, the fixture has an approximate efficiency of 199.6lm/W pre-driver, and 187.62lm/W after driver losses, giving it > 2.7uMol/J efficacy