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M-D Building Products

M-D Building Products 67106 36 in. Mill Aluminum Snap-on Sill Threshold Extender

  • Based on 900 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Tuesday, Nov 4
Order within 21 hours and 58 minutes
Available payment plans shown during checkout

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Color: Mill


Features

  • Made of durable aluminum
  • Used to extend inswing sill type thresholds
  • 2 in. W x 7/16 in. H x 36 in. L
  • Mill color
  • Easy install, snap into existing grooves on M-D sill thresholds
  • Cut with hacksaw to desired length
  • Installs onto M-D items 78691, 76265, 77792, 78600, and 78634

Brand: M-D Building Products


Material: Aluminum


Color: Mill


Product Dimensions: 36"L x 2"W


Item Thickness: 0.43 Inches


Brand: ‎M-D Building Products


Material: ‎Aluminum


Color: ‎Mill


Product Dimensions: ‎36"L x 2"W


Item Thickness: ‎0.43 Inches


Recommended Uses For Product: ‎Improving door sealing and insulation for all-season protection against drafts, moisture, dust, and insects


UPC: ‎043374671063


Number of Items: ‎1


Global Trade Identification Number: ‎63


Manufacturer: ‎M-D Building Products


Unit Count: ‎3.0 Feet


Part Number: ‎2121-7112


Item Weight: ‎13.4 ounces


Item model number: ‎MD Building - 67106


Is Discontinued By Manufacturer: ‎No


Size: ‎36 in


Pattern: ‎Solid


Shape: ‎Rectangle


Item Package Quantity: ‎3


Number Of Pieces: ‎1


Included Components: ‎MD Building - 67106


Batteries Included?: ‎No


Batteries Required?: ‎No


Date First Available: March 21, 2012


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Nov 4

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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Similar Products

Top Amazon Reviews

    • Storm door install
Color: Mill
Extension was easy to install and worked well with storm door installs on log cabin. I did have to rip a board to support but that was due to the unique way they trim log cabins. I'm sure installing on a regular door would be simple.
Reviewed in the United States on September 17, 2025 by Royce N Crocker Jr.
    • Perfect fit
Color: Mill
It fits our screen door's bottom perfectly. When I visited the neighborhood hardware store, they were sold out of the size I needed. I therefore placed my order for this part. I strongly recommend
Reviewed in the United States on October 10, 2025 by Grh
    • This works!
Color: Mill
Arrived quickly and solved our problem immediately. It popped right in and extended our threshold just as our construction crew said it would. Great product!
Reviewed in the United States on June 30, 2025 by Joey B.
    • Excellent extensions for Masonite door
Color: Bronze
Installed the bronze extension on a new Masonite door from H Depot. Slid on easily and securely. Used a scrap block of wood and a hammer before the jamb extensions were installed. Door was flat on sawhorses and jambs secured so they would not separate. Bronze color matched perfectly.
Reviewed in the United States on October 3, 2025 by Thomas
    • Solid Sill Extension Option
Color: Mill
Review Image by Greg J. Greg J.
I was able to saw down to 32 inches after installing a new storm door. The extension tapped right on with the help of a rubber mallet and held up against some test foot traffic. Only reason I'm not giving a perfect 5 stars is because the extension didn't really "pop in" so it can be kicked up with a little effort. Great overall item. ... show more
Reviewed in the United States on April 16, 2025 by Greg J. Greg J.
    • Great solution to storm door sweep gap
Color: Mill
Great solution for when you buy a Larson storm door from Lowes but the sweep doesn’t quite work with your jamb size. Took a bit of fiddling (trim for length, remove some old mortar so it would sit flush), but this worked wonders. Perfect result!
Reviewed in the United States on April 21, 2025 by AB
    • A few problems!
Color: Bronze
The elephant in the room? IT ARRIVED DAMAGED! Bent. When I paid extra for overnight delivery because of a next day install, I don't have time to ship it back and start over. When installing a $900 door, it should be PERFECT. It comes in 36 inches, but I needed only 32 inches, so I cut off most of the bad spot and had to touch up the bare metal silver color on the cut end with bronze paint, and finish the ends by filling them with caulk that matched, otherwise it would be left open for bugs or water (and not pleasing aesthetically). They don't sell the dark bronze color in any store I checked, just plain bright aluminum, so Amazon was my only hope for getting the dark bronze color. It's a very close color match, and it will be fine. It's a nice product. Gives a nice finished look (which is the way it should be in the first place), instead of just a blunt end of the threshold. SAGGING: I have read that the product is vulnerable to visible flattening or sagging after a while of usage caused by foot traffic, etc. and I agree. To solve that, I cut two pieces of pressure treat wood that ran the full length of the threshold for extra support, and secured it to the underside with Liquid Nails. Not easy to cut just right unless you have access to the proper saws to get the angles right. I hope it lasts for many years longer than I will. ... show more
Reviewed in the United States on October 28, 2023 by E. Schlueter
    • Fits perfectly
Color: Mill
Fits Frost King aluminum and oak threshold TAOC36A perfectly
Reviewed in the United States on September 23, 2025 by Mark M

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