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Endura Flap Custom Cat Door for Horizontal Sliding Windows

Endura Flap Custom Cat Door for Horizontal Sliding Windows

Regular price
$399.99
Sale price
$399.99
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Shipping calculated at checkout.
Brushed Aluminum
White
Black

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  • Custom-fit Endura Flap Cat Door for horizontal sliding windows
  • Durable aluminum frame with 3/16" clear safety glass, which is 59% thicker than the standard for enhanced durability and increased energy efficiency
  • Easy installation, perfect for renters with no permanent alterations needed
  • Comes with C-clamp lock, draft stopper, and weather stripping for security and insulation
  • Flap remains flexible in -40°F temperatures and stays sealed in 50mph winds
  • Custom orders are made to your specifications and are non-returnable
  • Approximately one month to build your custom pet door; reach out to our customer service team for expedited shipping options

Product Details


The Custom Endura Flap Cat Door for Horizontal Sliding Windows offers a practical solution for your pets to enter and exit as they please. This custom-fit cat door is specifically designed to fit seamlessly into your horizontal sliding window track, ensuring a secure and snug installation without any permanent alterations—making it perfect for renters.

Constructed with a durable aluminum frame and featuring Low-E safety glass, this cat door provides improved energy efficiency by blocking unwanted UV rays and infrared light. For smaller height ranges, the panel may be all metal instead of glass. The flap is lined with adjustable magnets to resist heavy winds and extreme temperatures, remaining flexible even in -40°F conditions and staying sealed in winds up to 50mph.

Installation is a breeze with the spring-loaded design, and the removable panel comes with a C-clamp lock, draft stopper, and weather stripping for added security and insulation. The cat door is available in three stylish finishes: white, bronze, and brushed aluminum, allowing you to match your window frame effortlessly.

The panels have a 3" spring-loaded height adjustment, so if you have a 48" track, for example, the panel you choose will adjust from 46"  49" inches. 

Not only will this cat door provide your pets with newfound freedom, but it will also enhance your home's overall aesthetic. 


Features:

  • Aluminum frame designed to fit into a window track width of at least 1" thick
  • Spring-loaded design ensures secure and easy installation
  • Adjustable magnets for heavy wind and temperature resistance
  • Removable panel with built-in cat door for flexibility and convenience
  • Sturdy locking cover keeps pets inside when needed
  • Available in white, bronze, or brushed aluminum to match your window frame
  • Comes with a C-clamp lock, draft stopper, and weather stripping for security and insulation

Benefits:

  • Easy to install and doesn't require semi-permanent installation
  • Removable panel benefits all owners, especially renters.
  • Don't need to make any permanent alterations to your window
  • Available in white, bronze, or brushed aluminum to match your window frame
  • Pets can enter and exit as they please
  • Made with durable, long-lasting materials

Size Chart

Flap Dimensions:

6"w x 11"h

The entry way your dog goes through.

Overall Panel Width

11 1/4"

How wide your panel is.
flap dimensions
epanel width
step over height

Step-Over Height

3”

The distance from the bottom of the panel to the bottom of your flap.
Flap SizeFlap DimensionStep OverOverall Panel WidthRecommended Pet Height
Small6" w x 11" h3"11 1/4"9" - 15"

Track Height Adjustment Range is the measurement of your window height from the lowest point of your track to the highest point. Review our Track Measuring Guide for more information. 

 

Choose the range that your track height falls into and when ordered you will be asked to give the exact height of your slider track inside very top to very bottom. In each case you will have 3" of height adjustment with the height you specify approximately in the middle of that range. Custom height option may take up to 4 weeks to special order the glass and build the panel. The ranges are:

Between 23"– 34"

Between 37"– 46"

Over 49"

CAUTION: If your measured track height is near the bottom of the adjustment range then you should review A Note of Caution.

Not sure if this is the correct flap size? Here is a measurement guide to help you out.

Find The Best Pet Door Size For My Pet

A

Pet Height: inches

B

Pet Width: inches

Please fill the above fields.

Additional Information

Flap Material

Flexible

Your Maximum Pet Size

Cats, Large Cats

Climate Suitability

Severe-4 Season

Type of Window

Sideways Sliding

Sealing Value

Very High

Wind Resistance

Very High

Installation Instructions

Installation icon Difficulty Easy
Installation icon Steps 04
Installation icon Time Required 0.5 hours
Installation icon Sections 02
Installation icon Flags 02

Parts

  • Horizontal Window Pet Door
  • Foam Weather Strip
  • Center Post Weather Seal Draft Stopper
  • Horizontal Window Clamp Lock
  • Screwdriver

Tools

  • Scissors
  • Flathead Screwdriver

Please read instructions & notes thoroughly before installation.

Step 1 Release Spring Mechanism

  • Loosen the height adjustment locks at the top of the pet panel with a screwdriver. This allows the spring mechanism to move freely up and down.

Step 2 Check Panel Fit

insert panel into track
  • To insert the panel into the top track, push up against the spring mechanism and swing the bottom of the panel up and over the threshold. Seat the panel on top of the small guide rail in the track.
  • You want to put the pet door in your track before applying any weather-stripping to ensure it fits.
  • If the panel fits well, proceed to the next step. See the FAQs if you have trouble.

Step 3 Apply Weather-stripping

apply weather stripping to panel
  • Once you’re sure the panel fits, remove it from the frame and lay it on its side on the ground.
  • Apply the foam weather-stripping by peeling back the paper and exposing the adhesive. Unroll it along the edge of the panel, pressing to ensure it adheres. Install on both sides, trim to fit with scissors.

Step 4 Install Center Post Weather Seal

apply center post weather seal fig a
apply center post weather seal fig a
apply center post weather seal fig b
  • The center post weather seal strip (draft stopper) should be installed on the inside of the home. It can be installed on either the back edge of the sliding window panel (Figure A) or the leading edge of the stationary panel (Figure B).
  • This strip prevents air from leaking between the sliding window and the stationary panel. Trim with scissors as needed.
  • Clean the edge of your window with rubbing alcohol before installing to assure a good seal.
  • Place the panel back into the window, then tighten the height adjustment locks to lock it in place. Installation complete!

LOCK DETAILS

Since you likely can no longer use your window’s original lock, we have provided you with an alternative locking method to keep your home secure.

Installing the window clamp: This clamp has a screw that tightens by hand to prevent the sliding door from moving beyond the clamp’s placement. For doors manufactured with the glass slider on the inside track, the lock can usually be installed on the door’s raised track.

window clamp on horizontal sliding windows

If you aren’t able to use the lock that comes with the panel: A great alternative to locking your sliding glass door is a Charley bar or dowel in the track. Both work off the same concept - they block the slider from opening. When engaged you cannot pull the sliding door away from the pet door panel.

Videos

How to Adjust the Magnet Strength on an Endura Flap



FAQ

How easy is this to install?

The spring loaded design makes installation of the cat door panel very easy. Once it is in place you can't remove it from the outside either, so it's safe and secure.

How do I measure to make sure that it fits?

You will need to open the window and measure from the deepest down inside the bottom of the track and all the way up into the track at the top. You will also need to measure how wide the track is, since the panel is 1" thick your track has to have at least that width to be able to accommodate it.

How strong is the seal on the pet door flap?

The magnets are stronger than your typical off the shelf pet door, so they will have to push the flap a bit harder to get it open. You can adjust the magnets in the beginning for training purposes by reducing their strengths, however you will lose some of the sealing power.

Is this just for cats?

Small dogs can also use the flap, as long as they can comfortably make it through a 6"w by 11"h opening.

Does this keep out drafts?

The flap seals extremely well so it is great if you are looking for energy efficiency.

How much does shipping cost?

Shipping is calculated at checkout.

Warranty

Warranty Type: Lifetime

Duration: Lifetime of the product.

Coverage: Defects in materials and workmanship under standard regular use.

Exclusions:

  • Damage caused by misuse or not using the product as intended.

  • Improper installation.

  • Damage caused by chewing.

View the full Endura Flap warranty policy. 



Customer Reviews

Endura Flap Custom Cat Door for Horizontal Sliding Windows

Brushed Aluminum / Custom Panel Height Edit

Endura Flap Custom Cat Door for Horizontal Sliding Windows

Size Chart

Flap Dimensions:

6"w x 11"h

The entry way your dog goes through.

Overall Panel Width

11 1/4"

How wide your panel is.
flap dimensions
epanel width
step over height

Step-Over Height

3”

The distance from the bottom of the panel to the bottom of your flap.
Flap SizeFlap DimensionStep OverOverall Panel WidthRecommended Pet Height
Small6" w x 11" h3"11 1/4"9" - 15"

Track Height Adjustment Range is the measurement of your window height from the lowest point of your track to the highest point. Review our Track Measuring Guide for more information. 

 

Choose the range that your track height falls into and when ordered you will be asked to give the exact height of your slider track inside very top to very bottom. In each case you will have 3" of height adjustment with the height you specify approximately in the middle of that range. Custom height option may take up to 4 weeks to special order the glass and build the panel. The ranges are:

Between 23"– 34"

Between 37"– 46"

Over 49"

CAUTION: If your measured track height is near the bottom of the adjustment range then you should review A Note of Caution.

Not sure if this is the correct flap size? Here is a measurement guide to help you out.

Find The Best Pet Door Size For My Pet

A

Pet Height: inches

B

Pet Width: inches

Please fill the above fields.

Flap Material

Flexible

Your Maximum Pet Size

Cats, Large Cats

Climate Suitability

Severe-4 Season

Type of Window

Sideways Sliding

Sealing Value

Very High

Wind Resistance

Very High

Installation Instructions

Installation icon Difficulty Easy
Installation icon Steps 04
Installation icon Time Required 0.5 hours
Installation icon Sections 02
Installation icon Flags 02

Parts

  • Horizontal Window Pet Door
  • Foam Weather Strip
  • Center Post Weather Seal Draft Stopper
  • Horizontal Window Clamp Lock
  • Screwdriver

Tools

  • Scissors
  • Flathead Screwdriver

Please read instructions & notes thoroughly before installation.

Step 1 Release Spring Mechanism

  • Loosen the height adjustment locks at the top of the pet panel with a screwdriver. This allows the spring mechanism to move freely up and down.

Step 2 Check Panel Fit

insert panel into track
  • To insert the panel into the top track, push up against the spring mechanism and swing the bottom of the panel up and over the threshold. Seat the panel on top of the small guide rail in the track.
  • You want to put the pet door in your track before applying any weather-stripping to ensure it fits.
  • If the panel fits well, proceed to the next step. See the FAQs if you have trouble.

Step 3 Apply Weather-stripping

apply weather stripping to panel
  • Once you’re sure the panel fits, remove it from the frame and lay it on its side on the ground.
  • Apply the foam weather-stripping by peeling back the paper and exposing the adhesive. Unroll it along the edge of the panel, pressing to ensure it adheres. Install on both sides, trim to fit with scissors.

Step 4 Install Center Post Weather Seal

apply center post weather seal fig a
apply center post weather seal fig a
apply center post weather seal fig b
  • The center post weather seal strip (draft stopper) should be installed on the inside of the home. It can be installed on either the back edge of the sliding window panel (Figure A) or the leading edge of the stationary panel (Figure B).
  • This strip prevents air from leaking between the sliding window and the stationary panel. Trim with scissors as needed.
  • Clean the edge of your window with rubbing alcohol before installing to assure a good seal.
  • Place the panel back into the window, then tighten the height adjustment locks to lock it in place. Installation complete!

LOCK DETAILS

Since you likely can no longer use your window’s original lock, we have provided you with an alternative locking method to keep your home secure.

Installing the window clamp: This clamp has a screw that tightens by hand to prevent the sliding door from moving beyond the clamp’s placement. For doors manufactured with the glass slider on the inside track, the lock can usually be installed on the door’s raised track.

window clamp on horizontal sliding windows

If you aren’t able to use the lock that comes with the panel: A great alternative to locking your sliding glass door is a Charley bar or dowel in the track. Both work off the same concept - they block the slider from opening. When engaged you cannot pull the sliding door away from the pet door panel.

Videos

How to Adjust the Magnet Strength on an Endura Flap



FAQ

How easy is this to install?

The spring loaded design makes installation of the cat door panel very easy. Once it is in place you can't remove it from the outside either, so it's safe and secure.

How do I measure to make sure that it fits?

You will need to open the window and measure from the deepest down inside the bottom of the track and all the way up into the track at the top. You will also need to measure how wide the track is, since the panel is 1" thick your track has to have at least that width to be able to accommodate it.

How strong is the seal on the pet door flap?

The magnets are stronger than your typical off the shelf pet door, so they will have to push the flap a bit harder to get it open. You can adjust the magnets in the beginning for training purposes by reducing their strengths, however you will lose some of the sealing power.

Is this just for cats?

Small dogs can also use the flap, as long as they can comfortably make it through a 6"w by 11"h opening.

Does this keep out drafts?

The flap seals extremely well so it is great if you are looking for energy efficiency.

How much does shipping cost?

Shipping is calculated at checkout.

Warranty

Warranty Type: Lifetime

Duration: Lifetime of the product.

Coverage: Defects in materials and workmanship under standard regular use.

Exclusions:

  • Damage caused by misuse or not using the product as intended.

  • Improper installation.

  • Damage caused by chewing.

View the full Endura Flap warranty policy.