Since its debut in 2013, and stunning victory of second place in the Asian Championships held in Thailand, and then the third place in Japan championship of 2014 / 2015, O.S. F3A motor reduction power unit used for competition has left a brilliant wartime career and this time has been evolved further .

The further development first lies in size up the reduction belt .The width of the second-stage reduction belt has been one sized up ( from 9mm to 11mm) , now can be strongly against tooth jump because of this change.

The second change is the floating structure . Floating structures , from those commonly used O -ring, is now changed to a structure using a dedicated vibration-proof rubber. Therefore, the high frequency sounds in flight is erased , it became further mild sound .

(OMA-4043-1160 motor does not change . )