This fan has made a huge difference in lowering the temperature of our bedroom. The outside air is cold at night year round, but my bedroom window faces towards another house, so there's no wind to force cooler air in.

I got this to pull outside air in at night and it's done a fantastic job. The airflow is strong and noticeable. It can lower the temperature of the room by about 5-10 degrees (depending on the weather).

Some things to note:

Only the 2020 version allows you to control each fan independently to exhaust or intake. I didn't realize this and was bummed out. If I need to change the air flow direction, I can just flip the fan around, but I hoped I could do it with a switch.

It's a bit loud on High. That brown noise old-school fan sound. We didn't like it at first, but our brains quickly tuned it out. If you're sensitive to sound, this might bug you.

It fits great in a horizontal window and the extender works great.

The temperature settings work, but I did notice that the fan can switch on and off repeatedly if the outside air temp matches the indoor temp.

Overall, BUY IT. It's great and I hope it holds up.

This fan is used and came with one piece that Im not sure what its function is, but in the good condition. all functions on the fan did not work. However, just to place it on my window for exhaust purposes-it work as intended. Im very happy with this purchase

This fan is light and VERY easy to install (it took probably 2 minutes to install). You can keep your screen down so it doesn't invite insects into your space. It cooled my stuffy, second floor apartment in about 3 minutes. In my living room I put it on intake at night and exhaust during the day. In my very narrow kitchen I just want more air circulation in general so I put one fan on intake and one on exhaust (the product contains 2 fans that are attached but that operate separately). I am very happy with this purchase because it lets me get fresh, cool air into my apartment while still allowing me to keep my windows open (unlike an air conditioner). It's a little noisy but I have heard a table top fan that was noisier, so I'd say the noise level is normal and reasonable. I have windows on only one wall of my apartment so there is no cross breeze. This fan creates a breeze in my apartment regardless. I'm really very happy with it.

I bought one. I liked it so well I bought another! I love all the features it has. Especially the reversing fans that can be controlled separately. The temperature setting that will turn the unit off once that temperature is reached. The high/low setting are great also. They fit perfectly in my windows with the extending/retractable side panels. I use them more than my a/c in the summer

The fan was really easy to set up and install. You don't even need the extender panels which block the open window and the fan can easily be put up and taken down as needed. I really like that there is an exhaust built in and you do not need to cycle through different modes. I purchased the digital display rather than the manual, and I wish I had bought the manual display instead. The thermostat on the fan doesn't work because it is built into the unit. I am using this fan to cool my apartment in the winter because my building uses radiator heat and it will get up to 85 degrees in my apartment even with my radiators turned off. However since the thermostat is built into the unit, the temperature controls always default off because it is 20 degrees outside yet 80 degrees inside. Because of the way the digital display is set up, I need to click the button 11 times to switch from low to high, or to go from high to off. If I had known this I would've purchased the manual display which is just a switch to change speeds. Despite the drawbacks of the thermostat and display it is still a good unit as it really effectively cools my apartment and is quiet enough watch tv or sleep when set at high or low speed.