Cat Mate Wall Liner - Compatible with Large Closer Pets, Cat Mate & Dog Mate Pet Flaps 221 & 357, White (Pack of 1)

If you are installing a cat door in a door you are all set with what comes with the cat door. But if you are going through something thicker like a wall you need one or more of these to complete the "tunnel" It fits the door perfectly and is easy to cut to the length needed and assembles easily. I highly recommend this product.

we used the extender to help us reach across to a catio from the window. we bought the door extension version that had 50 mm and used one extender to add 2 inches to go from window to catio on back porch (about 4 inches). it worked really well. i did use the foam included stripping to add between the extender to give it more rigidity. and then the back part was screwed into some wood we used in the window frame to give tension for it to be screwed into. overall, i'm pleased to have found this product. easy to use with the matching cat door.

We needed this because we had the cat door installed in the wall vs the door. Perfect fit. Worked out great with the cat door installation.

I purchased the electro-magnetic cat door and installed it in a door and it has worked well fo so I decided to order the exact same catdoor and install it in an exterior wall. To do this properly I ordered two Cat Mate 2 inch wall liners... to create a tunnel through the four inches of interior wall space. THEY ARE TOO BIG AND DO NOT FIT THE BCAT MATE ELECTRO MAGNETIC DOOR! IT HAS TAKEN ME HOURS TO FIGURE IT OUT BECAUSE WEBSITE DOES NOT ADDRESS THIS ISSUE. NOBODY ANSWERED THE PHONE! UNHAPPY HANDYMAN

The pet door is adjustable and easy to install. Durable so far.

It fit what I had already purchased to complete my installation.