... service life 4.Siemens motors for options Push-pull axial-flow industrial exhaust fanParameters: ModelDiameterBlades (mm)Air Flow ... efficiency test7. with CE, CCC, ISO certificate8.The fans may be widely installed in greenhouse,breeding room,workshop, ... air cooling and ventilation system.Applications: BTW series ventilation axial exhaust fans are widely used in agriculture greenhouse, garden, herding, ...