THERMWELL Frost King AC43H Air Conditioner Weatherseal Tape, 2-1/4 by 2-1/4 by 42-Inch

The THERMWELL Frost King AC43H Air Conditioner Weatherseal Tape is a simple but highly effective solution for sealing window AC units and eliminating the drafts, vibration noise, and dust gaps that tend to show up around older installations. The foam is dense enough to provide a firm, reliable seal, yet still compresses easily to fit uneven gaps without tearing or crumbling. At 2‑1/4 by 2‑1/4 inches and 42 inches long, the size is generous and works well for both side and top gaps on standard window units. During installation, the adhesive held securely without needing reinforcement, and once in place, the foam stayed put even through temperature swings and daily AC vibration. The material also rebounds well, maintaining its shape rather than flattening out over time. For anyone installing a new unit or tightening up an existing one, this weatherseal tape offers dependable performance, easy handling, and a noticeable improvement in insulation and noise reduction.

It is what it is-‘firm but not too firm. Good for filling in a gap.

Great item

So I bought an air conditioner and it's fine in my window but unfortunately the bottom half of the window is left wide open. In come this foam to the rescue. It's covered up that open portion and while it's not a perfect seal it still retain the coolness in my room. Besides the occasional bug that manages to slip by it the foam is decent.

This is perfect weather-seal for air conditioners. It's nice and thick, is easy to cut to fit, and it holds up well over time, especially since it's being put into a window where it's exposed to heat and sunlight and rain and wind. I'm very happy with it and highly recommend it.

I purchased this to fill the space between two windowpanes in a side-to-side sliding window after installing a window air conditioner. There was about an inch of space between the panes in a high wind area with typical winds of 20mph and frequent 30mph gusts in normal weather conditions. Everything I tried quite literally blew right out of place. I decided to give this a try and ordered the 2-1/4 inch size, so that I had plenty of room to squish it down and let it expand into place. It worked great! It was easy to install. I just pressed it down as sliding into place a little at a time and then adjusted it to make sure it was straight and aligned with the window to ensure it looks nice. The foam is sturdy, yet easy to squish to install. It took less than 5 minutes to seal both window spaces inside and outside. It expanded into place and is tightly packed. The winds (and dirt they bring) don't stand a chance!

What is nice about this product, is it is a medium density open cell foam. It is wider than most windows, allowing for trimming and a perfect fit. The thickness is great and it allows me to really seal the gap from where the lower and upper window pane cross.

Perfect fit for a.c