The Helios Fans RSK 400 is an automatic backdraught shutter designed for in-line installation within intake or extract duct systems. Suitable for use in any mounting position, this shutter effectively prevents reverse airflow to maintain system efficiency.
Constructed with a durable galvanized steel casing, the RSK 400 features lightweight aluminium flaps that respond to airflow direction. A stainless steel return spring ensures reliable automatic closure when air movement stops or reverses.
Its robust and corrosion-resistant design makes it ideal for ventilation applications requiring passive backflow prevention in both residential and commercial settings.