Ideal Pet ProductsAluminum Sash Window Pet Door, Adjustable to Fit Window Widths from 23" to 28", Chubby Kat 7-1/2” x 10-1/2” Flap Size

Unfortunately, this didn't fit my window, because I measured the wrong dimensions. So I wanted to give you some advice on measurements.First, the product measures a minimum of exactly 23 inches wide when compressed. And it measures exactly 28 and 1/4 inches wide (28.25 inches) when fully expanded. I actually measured this myself.This means that you should measure the narrowest opening of your window (usually the window frame itself) and make sure it's at LEAST 23 inches wide so the product can fit in.Once inside, it will expand to fit snugly against the inside track. The inside track is usually an inch or so recessed into the frame on each side. So that's the second measurement you want to make. The inside track width should be at MOST 28 inches wide.I made the mistake of measuring just the inside track of my window. It was exactly 23 inches wide. I thought this was what I should have been measuring. But the window frame bordering the inside of my window measures just 21 inches wide. And so the product was too big to fit in my window. I had to return it.This measurement stuff may seem obvious to you, but there's actually a youtube video showing someone measuring just inside track for a similar pet door product. And so that's what thought I had to do. It messed me up.As for the product itself, I am giving it 5 stars based only on what I've seen and felt. Keep in mind that I've not actually used it. The quality is better than what I had imagined. The metal parts are fairly thick. I think it has two glass panels, rather than cheap, see-through plastic ones. The functioning of the door itself is fine. It returns to center and doesn't get stuck open. There's also the 4-way locking mechanism on it. And the door itself is made of a hard plastic which actually looks good. It looks like the door seals tightly, and so I don't expect this product to leak much air. It comes with weather stripping and a draft seal. The draft seal should help to eliminate bugs as well. And it also comes with screws you can use to drill into your window frame so that you can lock the window to prevent burglaries.There are only a minor number of negative things I've noticed about it, and they're nothing to worry about. First, the metal parts are pointy and sharp at the corners, so watch how you handle them. Second, the dog door is made of a see-through hard plastic. I've not even used this door yet, but it's already showing tiny scratches on it. I believe that over time the door will turn cloudy due to scratching and constant use. But the door itself is pretty small, so it won't become too much of an eyesore. And every dog door I've ever seen has the same issue. Third, the white paint on the metal looks like it will scratch easily, but you can always repaint it.Also, about preventing burglaries... If you look online, there are a number of easy to use methods for locking windows that don't involve drilling a screw hole into your window frame. One of the ways I've seen is to buy a small diameter dowel rod. You just cut it and stand it up vertically on top of the lower window. The dowel rod will prevent the lower window from sliding upwards, if anyone tries to open it. A burglar would need pretty long arms to be able to reach in and grab the dowel rod.As for the cost of this product, I think relatively speaking it's a good price. I did a lot of shopping before buying this product. There are a lot of similar products out there selling in the $300 range. It's certainly a lot cheaper than those. But judging just by the materials and the simplicity of the product's design, I'd say it looks like it could be made for under $30. The fact that it costs $115-$130 is kind of surprising.And for the frugal minded amongst you, I wanted to tip you off that there actually are do-it-yourself guides on the web which detail how to make these products yourself. That has the benefit of letting you buy any type of pet door on the market and just making your own custom frame around it. There are perhaps better, more energy efficient or more weather proof pet doors to be had out there. You could even design your own door (in addition to the frame). It's all possible. But it requires time, effort, and the proper tools. Which is why I decided not to bother with making my own. Though, now I may have to, since nothing out there fits my window.Hope that helps.

I've had this for a sliding balcony door before and was very happy with it, so I bought one for the window. I love this because it's supereasy to "install": no tools and no drilling holes into doors, etc. Cats learnt how to use it instantly and love the freedom they get. And I love not worrying about deinstallation when it gets too cold or anything like that. In the beginning, the little flapping door might not perfectly shut after a cat/dog goes in or out. It breaks in and if not, trimming off a tiny bit of those bristles helped. Also recommend getting some insulation tape or similar if you plan on having it installed over a longer period of time as it does not perfectly seal.As for security of your home: It is relatively easy to break in if you're not making sure your window can't be opened from the outside as the regular window just "sits" on this. But that's just something to keep in mind and be prepared for.

I have a smaller window frame and wanted to set this up to an outdoor catio. I purchased a "like new" flap for the smaller window, with the hard plastic door (I wanted the flexible flap but it cost way more). Upon arrival, the frame was bent, the plastic weather stripping was missing, and the adhesive foam stripping was partially used. I just bought my own rather than hassle to send it back.It is easy to install. The lock is "meh" and could be easily broken by human force. There are some small seal concerns but they are minimal. I really wish I had a flap to slide in the door so my cat doesn't try to force it open when it's locked.

2020 - The window pet door arrived looking like it had been previously opened. But there was nothing missing and there was no obvious damage. The springs that allow this product to be firmly installed are quite strong. Be care when you turn the knobs that control the adjustment - you may be surprised at how fast the window sides move. This product is made for an aluminum sash window. With some patience and time, I installed it in our newer, double-hung wooden frame which has vinyl tracks. My window tracks are about 1/4" too narrow for this product to exactly fit. However, the tight side-to-side fit, courtesy of the strong springs mentioned above, and the two windows themselves, ensure a secure fit. Yes, this window could be easily removed by a burglar. We are installing a mesh cat enclosure on the outside of the house over this window so this is not a concern of ours. I removed the cat window until we have installed the outside enclosure. So far so good.july 2023 - we purchased this to allow our three cats to go outside into their "catio" - the wire enclosure mentioned above. at first they were hesitant - as cats are won't to be - but eventually they saw that it allows them to go outside 24/7. without human involvement. they love it. they use it multiple times in a day. the roof overhangs the enclosure so that even on rainy days they do not get wet. and it's entertaining to see them "launch" themselves from ground level to the top of a cat transport box and then out the swinging window. and these are not small cats. they "nail it" every time. i cannot speak to any other user's animals or intended use. but for us and our feline family this is perfect. this product has never failed. if your intended use is similar to ours i would highly recommend.

So sturdy! Much simpler to install then I thought it would be . My cats use this all the time and it’s still working exactly like the first day. 4 cats in and out all day and night not any issues at all.I do suggest that you measure carefully and measure the inside of your window . I didn’t do this and ordered the wrong size the first time , but I plan on giving it to a friend with a catio .