... motor YWF4E-500 air cooler axial motor fan ,air cooler motor fan ,500 air cooler fan,500 cooler motor . An overview of axial ... device.9. Most of External Rotor Motors have passed UL,ROHS, CE approval in Europe and CCC safety certificate in China ... external rotor motor YWF500—The diameter of the fan blade:500 mm—Material: Guard Grille: steel, phosphated and coated in ...