The Ducting Back Draft Shutter is an automatic mechanism designed to connect 2 separate air ducts in the construction of ventilation systems. It is equipped with metal wings that deflect when the air is in one direction and close as the air is drawn back. When there is no air, the wings are left closed with a spring.

• connects 2 separate air ducts
• prevent the return of treated air back into the room
• size: ⌀ 250mm