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Hon&Guan

Hon&Guan 4 Inch Backdraft Damper, One-Way Airflow Duct Damper 4 Inch Ducting Insert Backflow Preventer Duct Draft Blocker.

    • Based on 177 reviews
Condition: New
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This item's return window has been extended for the holiday season: Returnable until Jan 31, 2025

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Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, Nov 24
Order within 11 hours and 22 minutes
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Size Name: 4 inch


Features

  • MaterialThe 4 inch backdraft damper and the flap leaves is made of a galvanized steel, the axis are made of aluminum, while the spring are made of carbon steel.
  • Installation methodThe 4 inch duct damper has an opening of 100 mm and a length of 88 mm. When installed horizontally, the spring should be positioned horizontally so that it can be opened and closed optimally.
  • Wide applicationsBack draught valves can be inserted into ventilation ducts which are flexible or non-flexible. Designed for use with dryer vent backflow preventer, range hoods, bathroom fans, kitchen and other home HVAC applications.
  • Lightweight valve wingsThe valve wings open under the pressure created by the airflow; when the air flows in the opposite direction, it is automatically closed under the action of the spring, so as to cut off the flow.
  • Backdraft ShutterHon&Guan Draft Blocker designed to improve ventilation by preventing air from re-circulating when the fans are not in use, rubber ring ensure 100% closure and quiet closing.

Manufacturer: ‎Hon&Guan


Item Weight: ‎3.52 ounces


Product Dimensions: ‎3.46 x 3.93 x 3.46 inches


Country of Origin: ‎China


Size: ‎4 inch


Item Package Quantity: ‎1


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: March 24, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Nov 24

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Quiet and reliable
Size Name: 4 inch
I am using this back flow preventer inline with a mechanical fan as the purge for my sauna. Works great, installed some fine mesh hardware cloth over the end to keep out crawlies and doesn’t seem to affect the operation. Closes nice and smooth without the normal tinny bang. Super easy to install in a 4” access hole with a dryer diverter tip, perfect fit so it is true to size as advertised. ... show more
Reviewed in the United States on September 24, 2024 by nathan
    • Worked like it should
Size Name: 6 Inch
Works well
Reviewed in the United States on November 2, 2024 by les zimmerman
    • It works. Keeps the air drafts out.
Size Name: 6 Inch
Review Image by Fredrick Fredrick
Review Image by Fredrick Fredrick
Review Image by Fredrick Fredrick
Review Image by Fredrick Fredrick
Review Image by Fredrick Fredrick
I modified my exhaust vent and added this backdraft damper to reduce hot air and anything else from coming in when the unit is not running. It would have been better to install the damper in the far end of the duct (close to the window), but I would have needed to buy and modify a whole new window kit to make that work. Plus, my window does have a screen. The damper works well. install tip: Be sure to orient your damper so that the hinge is in the vertical position. This will ensure both flaps close properly with no air flow. ... show more
Reviewed in the United States on August 31, 2023 by Fredrick Fredrick
    • Cheap. Flimsy.
Size Name: 4 inch
Cheap and Flimsy. I can tell straight out of the box that any amount of pressure or debris and the damper flaps will get stuck open or closed. Spring is super weak. I'm not even going to install it. Quit making garbage. I would rather pay a little more and it be usable.
Reviewed in the United States on April 13, 2024 by Mnamesmith
    • just what i needed
Size Name: 6 Inch
Due to the construction of my home, i was unable to exhaust my portable ac unit through a window. I decided to run a vent through the attic access. Needed this to keep bugs from getting into the house. Works great.
Reviewed in the United States on September 28, 2024 by K.M. Kunz
    • Retaining Pin Broke
Size Name: 6 Inch
The butterfly vent works as it should, but I almost immediately broke one of the retaining pins as I was fitting it into the shed wall. I glued a small nail in its place, so an easy fix, but I was disappointed with the build quality breaking under the moderate stress of fitting it into place. Otherwise it was fine. It fit the vent properly, without any modification or shims. ... show more
Reviewed in the United States on July 28, 2024 by BDay
    • fit
Size Name: 6 inch-2pcs
Works like it's supposed to.
Reviewed in the United States on September 24, 2024 by Paul J. Sterle
    • Good value
Size Name: 6 Inch
Excellent quality.
Reviewed in the United States on July 29, 2024 by ALLAN

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