Repa Market 4 Inch Backdraft Damper – Galvanized Steel Draft Blocker/One-Way Airflow Vent Stopper/HVAC Exhaust Dryer Duct Connector – Inline Spring-Loaded Backflow Preventer for Secure Ventilation

Worked great. As described.

I bought a new house and the builders didn't install a damper so in the winter I could feel cold air coming in at my stove. This was easy to install just removed a spacer from the existing exhaust pipe and put this in. All the cold air stopped this is exactly what I was missing.

This damper works, but the spring is very weak. If you tip it anywhere past horizontal the doors fall open, so it can only be installed with the doors facing up or horizontally. Additionally if the doors open all the way to the center, the springs are not strong enough to push them closed again. I haven't run into an issue with this yet, but just noticed during the installation and will need to check at some point to make sure they are not stuck open.

Perfect, really does what it is meant to do. I have two bathrooms that I connected to the same exit vent with a y connection, and noticed that when one bathroom vent was on, the other would get some of the air going out. I put these in and neither bathroom gets the back flow any more.

Living in the deep south, after installing a new kitchen exhaust fan the down-draft from the attic was overwhelming. Especially since kitchen exhaust fans are located right over the stove and it is canning season! This item is wonderful. There is no more down-draft at all and combined with my wonderful new exhaust fan my kitchen is comfortable again. At least as comfortable as it can be when I am canning in the summer time in the deep south ;) Great product, shipping time was fast, installation was easy. Thank you!

Arrived banged up (damaged) and without the pin and spring.

Well made and blocker plates (2 half moon pieces) pivot well for exhaust under lower pressures, and allows very minimal backdraft air to enter.

The item that arrived was a Labeled ECOPRO brand 5in. Duct Damper and not a Repa Market branded 5'' Inch - Backdraft Damper. The big problem is that the ECOPRO has two springs an the metal flaps that are so strong that you really have to push a descent amount to have the flaps open and the Repa Market brand shows a single spring that is for both flaps and would allow the flaps to open or close with little effort. It is being returned as it is not the brand stated, or the product described. I will order the neverest® RK 5" Professional Backdraft Shutter Damper which uses only a single spring and is well made!