There's quite a difference.....can't rememebr for sure, but the sub-micro may generally have only 1 mounting hole per side while the micro has 2 per side. Best to go to the Manufacturer's website and check specs (dimensions). Tower Hobbies usually lists this type of info as well, but you're never sure how they measure it.....i.e. length.......to end of tabs, or to end of case?