- 4" Inch Backdraft Damper for Straight or Flex Duct. Bathroom Exhaust Fan. Kitchen Hood Exhaust Fan and Different Dryer Fan Backflow Preventer. Steel Damper with Aluminum Valve Flaps (4")

works great.stopes backflow of air

Absolutely fantastic. You hear that vent dropping sound when turning off the range hood. Not sure why was it so hard to find at local home depot tho

I purchased this backdraft gate for an exhaust fan in my basement. It’s opens with pressure from the fan and seals tight against the rubber gasket when the fan is turned off. It does exactly what I wanted and fit easily on my 8” duct pipe.

Noting - I'm a mech engr with a masters in HVAC / thermal engineering. I returned this item because upon my inspection, the coil springs are under too much tension, so the return torque (acting to close the two flappers) is too strong. Meaning this damper will excessively restrict duct air flow

This is a high-quality product great vent! I only returned it because it was the wrong size, but it’s been much better quality in which you would get at Home Depot!

Bought this to replace our original that finally failed. This new unit is built better than original and should last longer (original lasted 17 years).

The 2nd load of laundry I did after installing the damper came out of the dryer still wet. The damper was still functional, but I noticed that the hinges of the flaps caught on each other every few times I pushed them open. Good quality otherwise, but this malfunction was potentially dangerous as it was not allowing flow, but assumed to be open. I had to discard it and find a different solution.

I recently bought a couple of these for venting ranges. Appliance/fan dampers are pretty much universally inadequate and these are a cheap way to save on energy. I actually like to put one at the exterior wall and just after the fan on the inside. When I went to use these for a couple ranges I’m venting I noticed that the ring that the damper flaps onto is so oversized it #1 shrinks the opening more than is reasonable and #2 may collect grease and eventually get to the point where it’s inoperable because the damper will get stuck to the ring once it collects the inevitable muck.