4" HVAC Duct Manual Volume Damper Metal Adjustment Airflow Ducting Backdraft Damper for Air Ventilation System HVAC

This works well. When closed you get a little passing air, which in most cases is a good thing. It is easy to adjust the air flow and lock down.

Well made and the damper functions well. The only problem is the blade itself is smaller than the diameter of the body by a fair amount. Not a deal breaker but makes it a volume damper only. If you're looking for full close this isn't it. Always going to leak by.

Well made. Worked for our project.

Works great for smoke and heat control on a 4 inch stack on the grill I built.

Super heavy duty,was not happy that the tolerance were so tight.I had a very hard time joining it to 6 inch pipe.

I have struggled to balance the airflow from the HVAC system, as the original owner installed no dampers whatsoever. The temperature from room to room could vary as much as 15 degrees without dampers. This works as it should, and is easy to install. This is a damper, not a shutoff, so it doesn't completely stop airflow, it reduces the flow. It works well for the intended purpose.

used it as a fume extractor stopper. but doesn't have gaskets inside to stop the smell or fumes.. had to return. but if it had the gasket it would of made a very good product to get

Fancy. Works.I had to redesign and make a handle to close for my application. But I suspected that already.NOTE the valve does not close off tightly. It is a moving product, and I guess should be expected. But the gap was large. I will be installing some delta around mine because it’s coming on a dust collector. So I need the right closure.Will advise how that works.