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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 Reliable Home Products
Arrives Thursday, Apr 30
Order within 2 hours and 10 minutes
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Size: 36 in


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

Material: Aluminum


Brand: M-D Building Products


Item dimensions L x W x H: 36 x 2 x 0.1 inches


Color: Mill


Shape: Rectangular


Item Dimensions: 36 x 2 x 0.1 inches


Item Thickness: 0.43 Inches


Item Weight: 0.84 Pounds


Color: Mill


Item Shape: Rectangular


Item Form: Threshold


Material: Aluminum


Grade Rating: Residential


Brand Name: M-D Building Products


UPC: 043374671063


Number of Items: 1


Model Number: MD Building - 67106


Part Number: 2121-7112


Item Type Name: MD Building - 67106


Global Trade Identification Number: 63


Included Components: MD Building - 67106


Unit Count: 3.0 Feet


Manufacturer: M-D Building Products


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Apr 30

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.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Storm door install
Size: 36 in 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.
    • Total width 7 5/8 inch with extension.
Size: 36 in Color: Mill
Review Image by Sonny Jim Brown
This fits Frost King TS36A Heavy-Guage Aluminum Sill Threshold, Mill Finish, if hammered in from the side using a block of wood and wd40. Fit perfectly.
Reviewed in the United States on July 20, 2025 by Sonny Jim Brown
    • Perfect fit
Size: 36 in 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
    • MD Door Sill Extension
Size: 36 in Color: Mill
This is a perfect extension for aftermarket MD adjustable door sills sold on Amazon and many big box stores. It interlocks with a nearly invisible seam.
Reviewed in the United States on March 21, 2026 by Amazon Customer
    • Worked out eventually
Size: 36 in Color: Mill
This threshold extention was what I was looking for at an affordable price. Shipping was good. The only issue was the joining slot was crushed in at some points, making it impossible to affix to the existing threshold without repairing the crushed channel areas.
Reviewed in the United States on December 18, 2025 by ole1
    • This works!
Size: 36 in 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.
    • Useful piece
Size: 36 in Color: Mill
This saved my Sunday project lol. I was doing the siding and axel trim and I had to extend the threshold at my back door. Arrived the same day - project done!
Reviewed in the United States on April 6, 2026 by Greg K
    • simply amazing find
Size: 36 in Color: Bronze
amazing find! thank you M-D products and Amazon both what an outstanding product
Reviewed in the United States on March 3, 2026 by lifeid

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