8-Inch Professional Backdraft Damper Shutter Connector Duct

Well built. not perfect but 95% all you could ask for. Fits 6" duct nicely. Easy to install.

Works great and stops air in wrong direction, it even has a rubber seal which is a nice touch.

We have three fans in our master bath, which created an air circuit pulling either cold or muggy air into the house. Installing one of these in each duct has stopped that completely, stabilizing the temperature and humidity in the room (meaning our HVAC runs less often to compensate). As an added bonus, we didn't realize how much outside noise we could hear through those fans, but it's sure quiet now. The foam ring effectively silences the closing of the butterfly doors, so there's no closing noise when the fan turns off.Only nuisance issue is that the hinge pin sticks out enough on both ends that you can't insert this into the tapered collar end of a duct, nor can the tapered end quite fit into the ends of this fitting, so you have to cut completely through the duct to insert it. This issue is the only reason I don't give it five stars all the way around.

this dampers sized well for kitchen exhaust that was installed, spring could be a little softer but it opened enough for fan to do its job

The side which the damper halves open to is too short to fasten with screws. The damper swings far, and my 1/2 inch zip screws (on six-inch duct) were too long to allow the damper halves to swing unimpeded. If the people who built this thing added another inch to the 'downstream' side, this would be a useful product.However, since screws are forbidden in dryer vent installations (they snag lint, clog the pipe, and pose a fire danger), this product would be fine for that. But for anything where code calls for screws, don't buy this thing.

Works awesome I love it.

I like it. Works great, reasonable price, and easy to install.

These worked great for isolating 2 separate exhaust fans

Worked excellent and tested well for static pressure

Installed and works, keeps the cold out

would give it 5 stars if it was a little longer on the exit side to be able to use sheet metal screws to attach the ducting with out interfering with damper

Like the backflow seal and sturdiness of it ,works the way it should..

It is simple to install and works as advertised.