RSK.. Backdraft Shutters for In-line Fans

The RSK backdraft dampers are manufactured from steel with spring actuated aluminium flaps.

The patented SJK Smooth Flow backdraft dampers are constructed from injection moulded plastic designed with a low resistance gravity damper.

Both dampers form an excellent seal against backdraft when the fans are switched off. The SJK Smooth Flow damper has the lowest resistance of the two models. The pressure loss through the backdraft dampers has to be added to the system resistance before selecting the fan.