The manual volume damper is used for air volume regulation in an air ventilation system, and it is widely used in the HVAC industry. With that installed in your HVAC systems, you can easily control the airflow rate or close off an air duct if needed, to some extent, it will increase the energy efficiency of your system.SpecificationColor: SilverMaterial: 201 Stainless Steel / Aluminum / Silicone / RubberPort Outer Diameter: 125mm / 4.92 inchLength: 190mm / 7.48 inchPacking List: 1 x HVAC Duct Manual Volume Backdraft DamperAdvantageThe body of the damper is made from stainless steel and the flap blade is made from aluminum, rust-proof, corrosion resistant, and effectively prevents deformation.
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