400CM (157") Universal Window Seal for Portable Air Conditioner and Tumble Dryer – Works with Mobile Air-Conditioning, Easy to Install - Air Exchange Guards with Zip and Adhesive Fastener

I buy a new one of these each year, as they can get kind of gross after being exposed to outside for many months. The one I previously ordered changed their design to have a “universal” hose attachment, which of course did not fit the hose of my AC unit. I came back to Amazon to find one that has the zipper style opening and found this product. I don’t ever use the Velcro tape that comes with these, because I find the adhesive usually doesn’t hold up and seems to dissolve from heat-I buy the strong outdoors Velcro tape and it works perfectly with this! Setting it up was a pretty straightforward and easy process, and now that it’s been up a couple of months, I can rest assured that it is doing its job. It has been holding up wonderfully so far-the zipper stays taught around the hose exiting to the outside, and it is doing great at keeping the hot air outside instead of inside. I highly recommend measuring to ensure you get the right size, I measured and the fit was perfect. For these weird French windows, I absolutely recommend this product to set up your portable AC! They’re also quite easy to take down when summer is over, thought with the Velcro I have been using, I definitely have a lot of adhesive left behind that I will eventually need to address, but it’s totally worth it to be able to keep my apartment cool during the summer!

I was suprised how well it worked. I was worried that the velcro adhesive would be too sticky but seems like it will come off fine if I need to remove. I would recomend. Very easy to install.

Easy to install. Been using it for 3 weeks and the seal is nice and tight. Really made using our portable AC easy with casement windows

I've been trying to install my portable AC into a casement window for a week now. I have an outward-opening casement which opens vertically from the bottom.Before this, I tried a bunch of stuff to seal the window kit provided with my AC. Even after getting a sheet of plexiglass cut for the window, my AC still was leaking too much heat back into the room, and the plastic from the window installation kit even warped itself. This was my last hope... and luckily it worked like a charm! I'm pretty sure I even accidentally ordered one slightly too large for my window, but it still fits and works fine after rolling up some excess material.Installation was super easy albeit a little tedious -- the instructions were kind of bad and the video instructions online were very poorly shot (there's an animated video and a real-life demo, both of which not super helpful), but it was pretty much just a matter of cutting two sets of 4 velcro strips - one set for the casement, and one set for the window frame.Then you velcro the "seal", but annoyingly you have to pick a specific side to velcro to the casement vs the window frame, and the only way to tell which side is to follow the edge all the way until it tapers off at the end. It would be really nice if they would color the velcro on one side in order to tell that it's the "wide" side vs the narrow side.I mentioned that I got one which is slightly too big for my window - I rolled up the extra material in the area where I wasn't able to finish getting a velcro seal, and taped it up with some painter's tape. They say to use elastic for this purpose, but didn't provide any. It's not perfectly sealed in that area, and I expect I might need to do a better job of rolling it up if there's another big heat wave in the area.Installing with two hoses is just as easy as installing with one -- it's just an extra zipper in the seal. I pointed them both downwards.After turning on the AC, there is very little heat being leaked back into the room, which is perfect! Like I mentioned, this is so far the only solution that has worked for my casement window. The material is high enough quality that I don't expect it to degrade significantly in the near future, the zippers move pretty easily around the seal, and overall I'm pretty happy with it.

EDIT: While my review still stands, the customer service team did reach out and offer me a full refund for the trouble I have had with the product. I think that is acceptable and have decided to change my rating from a 1 star to a 3 star, taking into consideration the resolution. While I still will need to find a new solution for my AC, I at least am not out any money from this. Thank you HOMEE for actually caring about your customers! I wish the product had worked better for me and my window.I ordered this product a few months ago for my outward opening crank window. It seemed excellent at first and I was very happy being able to cool off my room, I have to leave the door shut many days which leads to very high temperatures and humidity. After maybe a month, the adhesive on the velcro tape essentially melted from the heat coming out of the exhaust hose. I was able to stick it back down, but this is a temporary fix and lasts only a couple days at best. The heat coming from the exhaust hose consistently melts the adhesive enough to pop open a large corner of the seal, rendering the product useless until I realize my room isn't cooling off and am able to fix it.This is a huge issue. It not only is inconvenient to have to check the seal multiple times a day to make sure there isn't a large opening into my home, but it is also making my AC have to run much harder to try and cool the room (which is essentially pointless while the seal is broken since all the heat is blowing back in). I can't trust leaving my AC run when I am not home either, since bugs or critters could come in through the hole, or my cat could get out.I have tried removing and reapplying the seal multiple times, each time I get the same result. I have tried changing the orientation of the seal, but nothing helps. The small amount of tension on the outer part of the seal, combined with the heat from the exhaust without fail causes the corner to pop off and make a large opening (8 inches or more) every single time. I cleaned the area well before applying, and I have since even removed the first set of velcro tape in the problem area, cleaned it a second time, and reapplied some extra velcro tape to that area, and it still has not solved the problem so I know it has nothing to do with dirt making it not stick or anything like that.Essentially, if you have an older outward crank window, be aware this is not going to be a permanent "set it and forget it" type of fix to your issue. Maybe this issue wouldn't happen with a bay style window, or an inward crank, I have no idea. All I can speak on is my experience of the adhesive not lasting up to the tension and heat. Definitely not worth the purchase. I should have just drilled a ventilation hole in the side of my home instead of this complicated and inferior seal.