there are 3 different UP Boards:
EL-CTR-0010 Control - HCS Power Board UP15 $47.14ea (green original boards with no wifi capability, used with the small wifi exhaust boards)
EL-CTR-0021 Control - HCS Power Board UP24 Dual Board $38.19ea (first series of dual board with wifi integrated. Used in field evaluated units only, do not put in quick books as a spare part)
EL-CTR-0024 Control - HCS Power Board UP25 Dual Board $40.07ea (current dual board with wifi integrated being used at present)