I have a fat older gentleman of a cat (16 pounds and climbing) who can still get through. I love these things and have installed them in several homes. It allows doors to be closed and cats to come through (or not when locked).

I could not think of anything I would like improved and that's saying something for an old engineer/critic. It does the job and is reasonably easy to install. I've got a utility room with a noisy furnace and the litter box, so I'm facing the daunting task of dremeling through the two sides of metal grating mounted in the door - but for the benefits, I'm willing to tackle this. The portion of the grating needing trimming is steel, so it says something that the benefits of the door outweigh the hassle of installation.

In another house, these doors allowed the cats to come and go from the basement where I put the litterbox. Incidentally, for that project I knocked together a table for the litterbox. The table was large enough to hold the litterbox and litter. And, if you are over 40, believe me: that is a whole new world of pleasure, not having to constantly bend down to "service" the litterbox.

In the current house, I did something similar by building a shelf (extending an existing shelf) since the room doesn't have space for a table. Again, its a magic world of civilization and luxury. Just do it, you'll never look back.

Works great for our purposes. We have a large closet/small room downstairs that houses all the litter boxes. I was tired of the smell drifting throughout the house so I decided to install this pet door to stop the odor from drifting about. It works great. Installed in about 10 minutes. Make sure if you are going to err, err on the side of cutting your opening too small. You can always make it bigger, you can't make it smaller. I cut it too big and had to shim the bottom so you couldn't see the opening around the pet door. Still works great though. Another tip, if your pets find the magnetic latch to be too strong, you can snap off the loose plastic piece on the bottom sill to expose three magnets. They are glued in but can easily be removed to lessen the pull on the flap. I took them all out since my door doesn't open to the outside of the house. All of our cats started using the door within 30 minutes and have had no problems with caught tails, etc. I would definitely recommend this product.

My cat absolutely LOVES this door. And so do I, because I no longer have to get up to open the back door to let him out in the yard when he cries to be let out and leave the kitchen door ajar until he decides he wants to come back in.

When I originally bought this door six months ago, it was listed only as a medium size cat door, and some people had expressed worries that their large cats won't fit through the Medium Size cat door: they thought they should go for the "Perfect Pet Tubby Kat Cat Door with 4 Way Lock And LEXAN Flap" or the "Cat Mate Large Cat Door," both of which had hard flap doors which have the disadvantage of coming down hard on a cat when s/he uses the door. Those of you who have large cats, maybe with the possible exception of Maine Coon cats, probably shouldn't worry about the Medium size door being too small for your cat: my cat is REALLY big: he is 13" high at he shoulders and weights 23 lbs [a bit chubby but not fat], and he doesn't have any problems getting through the door, and he does so with room to spare.

My cat is REALLY smart, but I did tape the flap above the door during the day for two days after it was installed to let my cat get used to going in an out of that "hole" in the door: the first time I shoved him through the hole, and he immediately got the idea. Then, after the first two days, I let the flap fall into place and shoved him out through the flap. No problem: he just knew what that "hole-with-a-flap" was for. If YOUR cat doesn't get the idea immediately, giving the cat a treat would probably help in getting him to use the door: to go outside, and, with the flap taped up on the inside, call your cat and give him a treat when the cat goes outside.

The door is REALLY a bonus. Raccoons come into my backyard at night, and they didn't need any training in learning how to use the cat door, and came in to eat the cat food which is right beside the back door. So I can use the door at night to keep the cat in and the raccoons out.

My cat quickly realized that the door panel on the cat door prevented him from going out. But I would suggest that you never lock your cat out by inserting the door panel while s/he is outside: it could confuse your cat if the door panel is inserted while s/he is outside because the cat can't SEE the panel as s/he tries to get back in, and the cat could easily just stop using the door to get back in if s/he is unsuccessful in getting back in a couple of times.

Installation is easy, but you WILL need a jigsaw to cut out the hole and a drill to punch out four holes at the four corners of hole you will cut out of the door. If you don't have a jigsaw or drill, your can probably rent them. And if you have no idea how to use either or both of these tools, you'll have to hire a local handyman or get a friend to cut out the hole in the door so you can install the door. But hiring someone shouldn't be expensive: cutting out the hole took about 15 minutes, and you don't need a handyman to actually install the door: installation is a breeze.

It took my cats about an hour to accept this door as part of their world. It leads to the downstairs, not the outdoors, so I cannot say how well it blocks the draft, but it fits my door well. Before I installed it, I used heavy duty clear packing tape to hold down the magnetic bar and I'm glad I did. The magnet still holds the flap shut, but I don't have to listen to the annoying ::clickity clackity:: of the 2:00 AM invisible cat-race-track (this being their new favorite obstacle). There are two rivets holding the metal bar onto the plastic flap and I constantly find cat fur wrapped around it. I feel bad knowing it's yanking out their fur, but I think taping over it would only be worse. Nice product for my purposes, though.
I have three cats, two of which are normal sized, the other is a 15 pound Maine Coon. He fits through this door, though it is a tight squeeze. If you have a super large cat (18+ pounds) I would suggest buying the next size larger.

I ordered the small, even though one of our cats is 18 lbs. The size of the next one up seemed like it might allow my dog to get through it. Sure enough, the fat cat can get through, though he does rub the edges.

What I did not like was installing it. If you use the plastic cover (meant to close off the opening) as a template, your hole ends up too large. I had to use shims to make it fit tightly enough in the opening after cutting. Also, none of the predrilled screwholes were large enough and I had to redrill them all to make them fit.

I installed this in a hollow door going from house into garage. Now that it's in it seems to work well enough.