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Vent Axia Back Draught Shutters for 315mm Flexible Ducting

· Backdraft Shutters Suitable for 315mm Large Volume Flexible Ducting
· Made From Galvanised Steel for Long Life and Low Corrosion Properties
· These Units Have a Positive Spring Return Mechanism. The Springs Are Carefully Selected for Positive Closure Without Undue Pressure Loss.
· Meets Current Building Regulations Approved Document F

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