do you mean ROAR approved?
If so, currently, the 36, 37 and 38's are too large in sub-c specification size and the membership is being asked in this next election to approve or not approve changing the ruling to allow up to 44mm in length of the cells. Currently, ROAR allows 43mm as the longest cell length but IFMAR has approved 44mm to allow the higher than 3300's in competition.
Currently, only 3300's are approved for ROAR competition but several 36 through 38's have been submitted and are awaiting membership vote as to the change in sub-c cell size. Of course, this will effect the chassis manufacturers as well.
I only hope the membership votes this election and offers their thought to the sub-c cell specification needs and the long term effects.
ROAR Promotions Director