• Elevate your SmartDoor™ installation with these tunnel extensions.
  • Compatible exclusively with the app-enabled SmartDoor™ Connected Pet Door.
  • Available in both Medium and Large sizes for a perfect fit.
  • Each extension increases tunnel depth by 2 inches.
  • Ensures safe and clear access for your pets through thicker doors or walls.

PetSafe SmartDoor Connected Pet Door Tunnel Extension

Extend Your Reach to Deep Wall Cutouts

Regular price $39.99

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Featuring a modular snap-fit design, each 2-inch stackable tunnel extension interlocks to cleanly line deep wall cutouts and protect your pet's entryway without requiring extra mounting hardware.

  • Elevate your SmartDoor™ installation with these tunnel extensions.
  • Compatible exclusively with the app-enabled SmartDoor™ Connected Pet Door.
  • Available in both Medium and Large sizes for a perfect fit.
  • Each extension increases tunnel depth by 2 inches.
  • Ensures safe and clear access for your pets through thicker doors or walls.

Installation & Fit

  • Interlocks directly onto the rear telescoping housing of the SmartDoor Connected main frame or into adjacent extension sections.
  • Adds 2" of continuous tunnel depth per stackable unit to cleanly bridge thick interior or exterior wall cutouts.
  • Connects via integrated snap-fit alignment channels; recommended to seal overlapping seams with silicone adhesive or weatherproofing tape for an airtight pass-through.
  • Fits inside the cut wall opening without requiring additional stud screws or dedicated mounting hardware.
  • Tool-free DIY assembly completed prior to final interior and exterior frame mounting.

Best Suited For

Ideal for:

  • Modular Stackable Depth: Line deep wall cutouts cleanly by stacking interlocking 2" tunnel extensions together without complex tools or extra hardware.
  • PetSafe SmartDoor Connected Pet Door owners installing into doors or walls exceeding standard frame depths.
  • Metal doors thicker than 1-3/4" or non-metal doors thicker than 2-1/4".
  • Available in Medium and Large sizes to match your existing SmartDoor Connected model.

Questions

How do I measure my old flap to order the right replacement size?

Measure the flap panel itself, not the hole it covers and not the outside of the frame. Take the width across the flap at its widest point, then the height from the top edge, including the section that sits under the retainer, down to the bottom edge.

Then count the holes along the top edge and measure the distance between the centers of the two outermost holes. Flap dimensions repeat across brands but hole patterns do not, so that spacing is usually what tells us which flap is actually yours. The size guide on the product page lists the flap dimensions for each size we carry, so you can check your measurements against it before ordering.

Can I buy just one flap for a double flap pet door?

Yes. On a double flap door the two flaps are separate parts, so you can replace one and leave the other in place. That is common, because the exterior flap takes the weather and the UV and usually wears out first.

Order the same size as your door and tell us which side you need if the two differ. If both flaps are the same age it is worth replacing them together. A new flap sits against the frame more tightly than a relaxed older one, and mixing the two can leave the seal uneven.

Does a replacement flap come with magnets and hardware, or just the flap?

Our replacement flap kits arrive ready to install. The flap ships with the parts needed to fit it to your door, so you are not sourcing magnets, rivets or retaining strips separately.

If you would like to add extra magnets for a firmer close, those are available separately as well.

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Product Details

Product Details

The SmartDoor Connected Pet Door Tunnel Extensions provide an additional 2" of depth per section to accommodate thicker door and wall installations. Designed specifically for the SmartDoor Connected Pet Door, these stackable extensions create a smooth, protective lining for your pet's entryway.

Customizable Depth Expansion
Standard pet door frames often fall short when installing through exterior walls, metal doors over 1-3/4" thick, or non-metal doors exceeding 2-1/4". Each tunnel extension adds 2" of depth, allowing multiple sections to be stacked together to cleanly line deeper cutouts without complex tools.

Technical Specifications & Features:

  • Precision Sizing: Available in Medium and Large sizes to match your SmartDoor Connected Pet Door.
  • Modular 2" Extensions: Each section adds 2" of tunnel depth for tailored wall or deep door fitment.
  • Multi-Surface Application: Recommended for metal doors thicker than 1-3/4", non-metal doors over 2-1/4", and full-wall cutouts.
  • Tool-Free Setup: Interlocking extensions attach quickly without requiring extra tools or complex hardware.
Sizing & Fit

Size Chart

FLAP SIZE FLAP DIMENSION ROUGH CUT OUT
Medium 7 1/8”w x 7 13/16”h 8 1/2”w x 10 13/32”h (non-metal door)
9 11/16”w x 12 11/16”h (metal door)
Large 11 29/32"w x 16 3/32"h 13 3/16”w x 19 3/32”h (non-metal door)
14 13/16”w x 21 1/2”h (metal door)

Do not know which size to get? Here is a measurement guide to help you out

FAQs

FAQ

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Customer Reviews

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Track heights exceeding 106 inches (107" or higher) may require additional shipping charges. Please provide your contact information for a custom freight quote, and our team will follow up during normal business hours.