Custom Endura Flap Thermo Panel 3e for Windows

SKU# 01PPCust

  • The Thermo-Panel 3e is the best all-around patio panel dog door for sliding glass doors
  • Insulated, dual pane, LoE glass, in sturdy aluminum framing
  • Features safe, energy efficient Endura Flap
  • No tools required for installation, perfect for renters and vacation homes
  • Adjustable heights and custom sizes to fit any sliding window!
  • Free shipping within the US

Note: These units are final sale with no returns.

View Warranty

Stock No: 01PPCust

Availability: In stock

Price From: $580.00
Loading options please wait..
>> View Size Chart <<
Price From: $580.00
Custom Endura Flap Thermo Panel 3e for Windows
The Endura Flap Panel is the foremost product on the market that combines style, comfort and reliability. It is specially designed with over a decade of research for the ultimate doggie door experience.

Hover over image to zoom

  • The Thermo-Panel 3e is the best all-around patio panel dog door for sliding glass doors
  • Insulated, dual pane, LoE glass, in sturdy aluminum framing
  • Features safe, energy efficient Endura Flap
  • No tools required for installation, perfect for renters and vacation homes
  • Adjustable heights and custom sizes to fit any sliding window!
  • Free shipping within the US

Note: These units are final sale with no returns.

In each case you will have 3" of height adjustment with the height you specify approximately in the middle of that range. 

Please note - If you order a custom insulated glass unit, it must be specially ordered which takes about 4 weeks. Since these are custom heights it's a final sale; no returns.

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

Note Don't think that the 12" width isn't enough unless you actually measure.  12" is Huge!  

Wondering how to measure your track? Review our Track Measuring Guide.

Flap SizeFlap DimensionStep
Stock No
Small #66" w x 11" h3"-5"11 1/4"01PPC06
Medium #88" w x 15" h3"-5"13 1/4"01PPC08
Large #1010" w x 19" h3"-5"15 1/4"01PPC10
Extra Large #1212" w x 23" h3"-7" (ships at 5")17 1/4"01PPC12

Don't know which flap size to get? Here is a measurement guide to help you out

Minimum and Maximum heights vary by flap size. Here's the info

Custom Height: Minimum & Maximum Heights
Small #635"100"
Medium #842"107"
Large #1048"117"
Extra Large #1246"123"

Thermo Panel 3e - Custom Height

This pet door by Endura Flap, is available for those customers who have unusual height sliding windows not accommodated by the three adjustment ranges of the 'standard' height Thermo Panel 3e and also for those customers who would like to install a patio pet door in a sideways sliding window.

We generally recommend some other pet door type if possible because custom products have some very significant disadvantages. First, they're not returnable and it is certainly true that customers usually have a very good reason when they need to return a product. We don't like to have to say 'no'. Second, even though the charge for the custom product is immediate, the delivery is considerably delayed because the custom height insulated glass unit takes 3-4 weeks for delivery from our tempering plant. We will give your custom order first priority in manufacturing.

Incidentally, if you happen to have a track height that's close to the bottom end of our lowest standard adjustment range, you may be able to utilize the 'anti-whoops' feature of our panels to avoid the need for a custom height. 'Anti-whoops' allows you to shorten the adjustment range by up to about 1" and that might be enough to get you into the 'standard' height range you need. Measure carefully!

The spring-loaded height adjustment range of the Thermo Panel 3e is 3". So you don't need to worry about specifying an exact adjustment range. We'll put your specified height around the middle of that range. So, for example, if you measure 88", we'll build your Thermo Panel to adjust to something like 86" - 89"


The Thermo Panel features will only be summarized here. For a more complete explanation please refer to our regular Thermo Panel IIIe page.

Most important is our patented, award-winning Endura Flap™. Nothing seals and insulates so well or lasts so long as this innovative pet door flap. We encourage you to watch the video on the 'video' tab for the full story. By the way, here's what you get with the typical pet door flap.

A second patented feature of our Thermo Panel and Quick Panel patio pet doors is the 'user-adjustable step-over'. With this feature you have much more flexibility in the size dog the pet door will accommodate. No other patio pet door has this important feature.

A sturdy locking cover comes with every Endura Flap pet door. The dimensionality of this cover--it's not just flat--actually increases the strength to the equivalent of a 1/16" steel plate.

Minimum and Maximum heights vary by flap size. Here's the info

Custom Height: Minimum & Maximum Heights
Small #635"100"
Medium #842"107"
Large #1048"117"
Extra Large #1246"123"


Important!  Custom height orders may not be made by phone.


** Special Bonus Offer!  Add an Amazing Bug Warden at about 20% off Regular Retail

The Bug Warden is a revolutionary new product that allows you to close your screen door completely while allowing access to your pet door. If you're opening the sliding window for ventilation during the warm months, this is for you. As a once-only offer, you can purchase the Bug Warden for 20% off with your purchase.


Customer Reviews

Set Direction
  • Awesome-ness review by Louie
    5 5 Awesome-ness

    This door is a thing of beauty and class. I love it! It fits nicely in my window. Theres no extra noise. There is no outside elements coming in. I would buy this again in a heartbeat. Two thumbs up endura flap!!

    (Posted on 9/10/2018)

  • amazing review by scott
    5 5 amazing

    This door was so well worth the money spent. It is so insulating and efficient. I have my air conditioning on and it does not escape through the door. The outside air does not come in either. It was built to fit my window perfectly. I am so impressed with this quality of the door. My dogs are so happy!!1

    (Posted on 9/6/2018)

  • Perfect product.. review by mitchie
    5 5 Perfect product..

    My windows open side to side and no one makes a window for cats that goes side to side except for Endura. It is everything I wanted. It is dual pane, stylish, sturdy, energy efficient ect. The flap is staying shut with the weather and the wind. I could not ask for anything better.

    (Posted on 6/15/2018)

  • Works great review by Cheryl
    5 4 Works great

    So, you see...apparently my sliding door isnt a "normal" size. I thought all sliding doors were more or less standard and mine fell outside that range. Customer Service worked with me and were very helpful in getting my door sized correctly. I received it a few weeks later and it works perfectly. I just wish that they made panels in standard sizes...

    (Posted on 2/21/2018)

  • Works great for horizontally sliding widows review by Mia
    5 5 Works great for horizontally sliding widows

    I wanted a cat door for a window that opens side to side. After a lot of thought and conversations with customer service, I have finally decided on this one. It was a bit scary to order because it is custom and non-refundable but the customer service staff was able to answer all my questions and helped me place the order. I just received it and it fits great in my window!

    (Posted on 12/27/2017)

Weight 1.0000
Manufacturer Endura Flap
Your Maximum Pet Size Cats, Large Cats, Small Dogs, Medium Dogs, Large Dogs, X-Large Dogs
Climate Suitability Severe-4 Season
Sealing Value Very High
Wind Resistance Very High
Type of Window Sideways Sliding
House Locking Method C-Clamp Lock
Frame Material Heavy Extruded Aluminum
Custom Heights Available Yes
Can Fit Sideways Sliding Windows Yes
Track Width Minimum 1"
Built-In Adjustment For Small Measuring Errors Yes
Tools Required For Installation none
Patented User-Adjustable Step Over Height Yes
Employs Patented “Endura Flap” Yes
Insulation Value High
Possible to Add Additional Magnets for Greater Wind Resistance Yes
Flap Material Engage
Flap Design Single, One Part , Flexible, Insulated Flap
Flap Colors Clear
High Aspect Ratio Yes
Flap Thickness 7/8"
Award Winning Design Yes
Flap Warranty (if separate) 15 years
Locking Cover Material Dimensional ABS
Can Be Installed In Dual Pane Glass Sliding Glass Door, Sideways Sliding Windows, Single Pane Glass Sliding Glass Door, Vinyl-Framed Sliding Glass Door
Dual or Single Pane Dual Pane
Low “E” Coating Yes
“Draft Stopper” Included to Seal Stationary & Sliding Panel Overlap Yes
Warranty Period 15 years
Return Period Not Returnable
Manufacturer's Restocking Fee 0

The Endura Flap Pet Door



The Thermo Panel 3e Patio Panel Pet Door



Removing Side Magnets



Variable Magnetic Resistance



Adjusting the Step Over Height



The Leaf Blower Test



Get a Discount on a Bug Warden (an essential accessory if you ever leave your sliding door open for ventilation)

Although this video illustrates how to install the panel in a sliding glass door, the installation will be the same for your window.

Click below to expand:

You would need to measure from the deepest part in the bottom track to the deepest part up inside the top track. Also the panel is 1" in thickness so make sure that your track is at least that wide to be able to accept the panel.

That is how far from the bottom of the pet door the flap actually starts. So it is what your pet would have to comfortably clear in order to get out and in.

These are excellent for insulation as they have dual pane low-e glass, and the Endura flap pet door which happens to be one of the best sealing and energy efficient doors on the market.

It is meant for more of the DIY (do it yourself) type of installation. In the really taller heights it can be a bit tricky since the panel is tall and heavier, so it is helpful to have an extra set of hands. I would suggest taking a look at videos tab for a better ideal of just what the installation looks like.

Yep! We include a closing cover that you slide in place. The tracks are located inside so you don't have to go outside in bad weather to close it off.

We include a clamp lock for panels under 80.25" and a foot lock for all panels over 80.25". You can also use a charley bar, or the old dowel in the track method. All of these different mechanisms work off the same principle that when in place the prevent the sliding door from being pulled away from the pet door panel.

No, the panel is held in at the top with a spring loaded adjustment piece. Once the thumb screws, located on the inside, are tightened you can't slide down that piece in order to remove it.

The framing is a heavy gauge aluminum.

We do have the Thermo Panel 2e panels, but the largest flap is on 7" x 7" in Pet Door version. So it is recommend more for cats and pretty small dogs.

Being that they are custom and we have to special order the glass it can take roughly 4 weeks for delivery.

Yes, you can order a Thermo Panel to accommodate your shorter door. When choosing the Track Height Adjustment Range, select "cust ht under 74 3/4 and then you will be prompted to enter your track height. We will build a panel to your specifications.

Write Your Own Review

You're reviewing: Custom Endura Flap Thermo Panel 3e for Windows

  • 1 star
    2 stars
    3 stars
    4 stars
    5 stars

* Required Fields

Patio Pacific Inc Endura Flap™ Pet Door Warranty

To the original purchaser, Patio Pacific Inc warrants this product and all of its component parts to be free of defects in materials or workmanship for a period of 15 years from the date of delivery to the customer.

Endura flap assemblies are warranted for a period of 15 years. Endura Flap™ assemblies employed in commercial kennels are warranted for a period of 3 years.

Damage caused by accident, improper installation, abuse or normal wear, including damage by pets or glass breakage, is specifically excluded from this warranty.

Defective materials returned to Patio Pacific Inc, together with proof of purchase, will be repaired or replaced and returned to the customer free of charge.

Pet doors of other manufacturers installed in Patio Pacific products are covered by the warranty of the other manufacturer and not by Patio Pacific Inc.