Thermo Sash 2e with SureFlap Microchip Cat Door

Regular price
Sale price
Regular price
Sold out
Unit price

  • Combines a highly insulating panel and technology of rfid cat doors
  • Fits sash windows from 22"-43" wide and tracks at least 1 thick
  • Prohibits unchipped animals from entering your home
  • Automatic cat doors sense from the outside only
  • Installation does not require any permanent alterations to the window

The SureFlap Thermo Sash 2e Microchip Cat Door for Windows is an innovative pet door panel that combines supreme insulation and reliable microchip sensing technology. The sensor scans your pet's microchip and unlocks from the outside, ultimately preventing any unchipped, intruder animals like stray cats and raccoons from accessing your home. Not only will this window Sureflap microchip cat flap keep your cats safe from unwelcome critters, but it also ensures that they still have the freedom to come and go as they please.


  • Aluminum-framed panel is engineered with dual-pane glass to ensure thermal quality.
  • Fits sash windows from 22"-43" wide and tracks at least 1 thick.
  • 5 5/8"x 4 3/4" flap is a clear, rigid plastic line with brush weather stripping to prevent drafts.
  • SureFlap cat door programs up to 32 different microchips/RFID collar keys.
  • If your pet is not chipped or is waiting to be chipped, you can purchase an RFID collar key in lieu of the embedded microchip.
  • Any cat can exit the microchip cat door window insert, but only programmed cats can enter.
  • Battery-powered door uses 4 AA batteries with a battery life of around 6 months.
  • When batteries are low, an indicator light flashes every 5 seconds. Replace the batteries when this light is flashing. When the batteries die, the door defaults to the locked position, which could leave cats stuck outside.
  • Features a 4-way locking device (in or out only, or completely locked or unlocked) that will override the electronics when switched to the manual lock setting.
  • Available in white or dark bronze.
  • Inserting the panel does not require any drilling or permanent alterations. Installing the actual Sureflap cat flap into the panel is required, as this does not ship pre-assembled.


  • Prevents strays, and other unwanted critters from accessing your home.
  • Ensures your cat's safety inside their own home.
  • Sash window cat door panel provides excellent energy efficiency and insulation.
  • Great solution for cats who do not enjoy wearing collars.
  • Cat door in windows mean you don't need to cut holes in your home.

Size Chart


Flap SizeFlap DimensionFrame HeightHeight to Raise Window
Cat Flap5 3/4" w x 4 3/4" h11 1/2"12 1/2"


Adjustment Ranges:

  • 21 3/4" - 25" Custom Order
  • 24 3/4" - 28"
  • 27 3/4" - 31"
  • 30 3/4" - 34"
  • 33 3/4" - 37"
  • 36 3/4" - 40"
  • 39 3/4" - 43"


Pet door has 1" framing, measure your track width to make sure that your window will accommodate the sash.

The SureFlap Pet Door works with all identification microchips supplied by your vet and SureFlap RFID collar tags.

Final Sales: Adjustment Range 21 3/4" - 25" are final sale and cannot be returned. All Extra Large sizes are also custom and non-returnable.


Additional Information

Frame Material


Warranty Period

3 years

Return Period

90 days (except for custom height ranges)

Door Open Type

Unlocks for the key signal and pet pushes open

Your Maximum Pet Size

Cats, Large Cats

Controls Access

From Outside Only

Operates On


Flap Opens

Pet Must Push

Type of Window

Sash (Up & Down)

Flap Design

Single, One Part, Rigid, Thin Flap

Can Be Installed In

Dual Pane Glass Sliding Glass Door

Additional Lock

4-Way Lock

Number Pets


Activated By

Implanted Chip, RFID

Installation Instructions


Step 1: Loosen the thumb screws at the end of the sash. This allows the spring mechanism to move freely side to side.

Step 2: Insert the sash into the window track. Push against the spring mechanism and swing the opposite end into the opposite window track. Gently release. Tighten the thumbscrews. If the pet door sits properly, remove the pet door to put on the foam weather-stripping in step 3.

Step 3: 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 the top and the bottom. Trim to fit with scissors.

Step 4: Mount the draft stopper vinyl weather strip. This strip prevents air leaking between the window frame when raised to accommodate the sash. Trim to fit with scissors.



For a permanent lock, install a wood screw in the track immediately above the window on both sides. You will no longer be able to raise the window.

For a temporary lock, place a removable wooden dowel or charley bar in either track above the window.



Remove the screws on the top and bottom closest to the edge of the pet door. Then slightly loosen the screws closest to the glass. Next, slide off the side piece, then the flap assembly. Rotate the flap assembly (essentially flipping it upside down) then slide it back in. Make sure the locking cover is on the same side as the thumb screws. Replace the end spacer and screws.



Make sure you place steps or ramps leading to your pet’s door at a height that works! When they go through the flap, the top of the flap should be at least 1” (2,5 cm) higher than the top of their back. Watch your pet and adjust as needed to keep them comfortable.



Step 1: After testing the panel to make sure it works in your window and confirming that the SureFlap will work with your pets, you are ready to attach the pet door to the hole in the panel.

Step 2: Find the 2 middle length screws in the SureFlap box.

Please Note: Thumbscrews should be on the same side as the controls of your SureFlap. Installing your SureFlap with the controls on the outside of your home will damage the pet door and void SureFlap’s warranty.

Step 3: The trim frame and screws will go on the outside of the panel. Place the side with the locking controls on the inside of the panel. The controls will need to be on the same side as the thumbscrews. You can then follow the remaining instructions for either the vertical or horizontal panels.



You can choose to secure your pet door in your track with screws. This can be done by drilling screws at an angle in the top and bottom tracks. We recommend doing this from the outside to minimize damage to the sliding glass door frame. One-way screws will prevent tampering or removal of the panel from the outside.



Some stationary panels can be unfastened and moved over to one side so that you can install the pet door panel between the jamb and stationary panel. Avoid damaging your sliding glass door by checking that your door can move and that you can reinstall it properly before trying to uninstall the unit.

You will still lose space in your slider to move through, however you will be able to use your existing sliding door lock to secure your home. Installing your pet door this way is also great if you already have an alarm system in place. If your sliding glass door slides on the outside track, using an alternative lock might not be possible so this allows you to still lock your door.

Training Sessions 

Getting Started: Some pets will take longer than others to acclimate to their new door, so patience is key! Never push or shove your pet through the door (this will only develop negative feelings). Instead, follow these training tips + tricks to help introduce your pet to the door gradually.

Limit training sessions to no more than 10 minutes at a time. Two well spaced out sessions per day should be the maximum.

Hold the flap all the way open for your pet at first; then a little less each subsequent time so your pet learns to push through on their own. Stay consistent with verbal encouragement and treats for best results.


Teaching Your Cat to Use Their Door

Step One: Introduce your cat to the door by putting your hand through it so they know how it works. Have them inspect the new cat flap to get used to the look and smell (this is a great time to program your cat’s microchip!).  

Tip: You can wipe your cat’s face or body with a cloth and wipe the door with the same cloth to give it a more familiar scent. 

Step Two: Some cat doors make a slight clicking noise when opening and closing which can scare timid cats. Try manually opening and shutting the flap slowly to familiarize your cat with this noise. 

Step Three: Get your kitty’s favorite treats or toy ready! Start by using a treat to encourage your cat through while holding the flap open for them. Once they are comfortable, start lowering the flap on them as they walk through for their treat.

Tip: Be sure to train your cat using the actual door height - meaning raise the door enough so it resembles how high it will be once installed.

Tip: If you have a door with non-removable magnets, putting some painter’s tape over the magnets can help decrease the magnet attraction strength temporarily for training purposes.

Step Four: Always make sure to reward your cat with praise (and maybe another treat) when they pass through the door.  Remember: training can take a considerable amount of time. There is no standard practice as every cat is unique.


Quick Tips

- For especially timid cats, temporarily tape it up out of the way while they get used to the idea of walking through the tunnel.

- Clear flaps may confuse pets as they might think the flap is a window. Try putting a piece of masking tape on the clear flap to distinguish it from a window and reinforce to your pet its use as a door.

- Magnetic and weighted flaps have additional weight which may be difficult for your pet to push through. Fix this problem by gently pushing the door to assist your pet as they go through or removing the magnet until your pet gets used to the full weight of the door on their own.

- If you plan on installing more than one pet door, use the same flap if possible for consistency.

- Electronic flaps make a small clicking noise when the flap is activated that may frighten timid pets. The best way to remedy this problem is to positively reinforce this sound in your pet’s mind.

- Praise your pet when they come near the door and hear the activation noise.

- If this does not work, disable the electronics with “training mode” and have your pet use the door manually for a week or so while getting acquainted with the door.

- Consistency is key! Stay consistent both in your training methods and your choice of pet doors. If you have multiple pets the first to learn will often demonstrate  for the others!

- When your first lock the flap shut, introduce your pet slowly rather than letting them “learn the hard way” by running into it.


How to Measure Your Sash Window for a Pet Door


What 3 things do I have to know/measure when choosing a pet door for sash window?

Track width, Height you can raise the window, How wide the window is from left to right.

Is there a version of this panel that has the DualScan Microchip Cat Flap?

Yes, the Thermo Sash 2e with the Sureflap DualScan Cat Flap is a great product and you can find it here.

Will the door still work if my cat does not have an implanted microchip?

If your cat does not have any microchip identification or a microchip number, you can attach an RFID door key to their collar instead. With the RFID key, the microchip reader will still be able to detect your cat. We recommend you get your cat microchipped as soon as possible since the unique code in a cat's chip will help prevent them from getting lost and help verify your pet identities.

Does this microchip pet door connect to the Sure Petcare app?

No, you would need to get the Sureflap Microchip Pet Door Connect for Doors.

I don't have a window track to install a cat flap into and I do not want to cut a hole in my wooden door. What do I do?

You can get a glass installation adaptor that will allow you to install the Sureflap Microchip cat door and the Sureflap DualScan Microchip cat flap into window panes. You can also get a wall installation kit and cat flap tunnel extensions to make your cat door into a wall entry pet door. Make sure you get the right wall kit as the Sureflap microchip cat flap connect pet door has a different wall kit and tunnel extender. Ordering the wrong one may interfere with your door's normal use.

Is there a Thermo Sash panel with the Cat Mate Elite cat flap?

No, there is no version of this product with any Petsafe or Cat Mate microchip cat flap.


Patio Pacific Warranty

Endura Flap products have a lifetime warranty against defects in materials and workmanship under standard regular use. Damage caused by not using the product as intended, improper installation, and chewing is not covered under this warranty.

SureFlap™ Cat Door Guarantee

Guarantee: SureFlap™ microchip cat flaps carry a 3-year guarantee from the date of purchase, subject to proof of purchase date. The guarantee is restricted to any fault caused by defective materials, components or manufacture. This guarantee does not apply to products whose defect has been caused by normal wear and tear, misuse, neglect or intentional damage.

In the event of a part failure due to faulty parts or workmanship, the part will be replaced free of charge during the guarantee period only. At the manufacturer's discretion, a replacement product may be provided free of charge in the case of a more serious malfunction. Your statutory rights are not affected.

Disclaimer: The SureFlap™ microchip cat flap incorporates selective entry features which have been designed to minimize the risk of unwanted animals entering your home. However, it is not possible to fully guarantee the exclusion of all other animals in all circumstances.

In the rare event of an unwanted animal gaining access to your home, SureFlap cannot accept liability for any damage or inconvenience which may be incurred.

Warning: The motorized catch and manual lock are provided exclusively to prevent the entry of unwanted animals and is not a security device. SureFlap Ltd cannot accept liability for unintended use and the owner of the product accepts full responsibility for supervising the access in and out of the home that it provides.

In households with children, it is essential to include the cat flap in child-proofing considerations. Misuse of the cat flap by a child may result in the child coming into contact with potential dangers. For this reason, young children should be monitored at all times when in the immediate vicinity of the cat flap.

Caution: Prior to installation, it is the responsibility of the user to consult all building codes which may influence the fitting of the cat flap and assess the suitability of a given installation. The user must also consider potential hazards present inside or outside the cat flap as well as the impact that subsequent modifications to your property may have on the existence and use of your cat flap. It is recommended that these assessments are conducted in consultation with a construction professional.

Do not install SureFlap™ in a fire door as it will render the fire door unfit for purpose.

Customer Reviews

Based on 5 reviews Write a review