Hlg qb18 and qb35 are “emerson boards”. They contain red, deep red, and far red diodes to increase photosynthesis using the emerson effect (learn more in “the far red thread” on riu). The qb18 and qb35 Are the same boards, the 35 is the full kit, the 18 is just the board. The 96s already have most of what is in the 18/35 built-in, just need to have some add’l far red.
End of Day (eod) far red (see far red thread), refers to the “initiator effect”, which basically instantaneously puts the plants into nighttime/sleep mode, when the far red is turned on for a few minutes at lightsout (normally takes plants a couple hours to do under normal conditions). I push my plants pretty hard during flowering, so i let them sleep longer, but some guys use the quicker initiation of sleep mode to lengthen lightson by up to 2 hours, which can reduce flower cycle duration and/or boost yield....