Hobbypower GemFan 6X3 6030 Multirotor CW CCW Propeller QAV250 Quadcopter Prop Black(pack of 4 pairs) GemFan 6030 Multirotor CW + CCW Propeller 2 blade style with a 5mm center hub. GemFan produces excellent propellers for airplane and multirotor uses. They are all well balanced from the factory and provide excellent and smooth power. You will not be disappointed with GemFan products on your aircraft.