nu air single hung alum windows (balances)

Thanks for posting. Sounds like you have a 35" block & tackle balance. Now you just need to pick out the top and bottom fittings in order to determine the Series. You will also have to weigh your sash to determine the right stamp option.

I recommend that you look at our Channel Balance Home Page and follow the steps in order to find the Series that best matches what you have.

Hey, thanks for posting. I've narrowed this down to two possible channel balance Series: either our Series 380 or our Series 385 balances.

Now, as you can see, there is only one difference between these two Series, and that is their bottom shoe. The Series 380 uses the 15-005 while the Series 385 uses the 15-004. I can't quite tell what you have based on your pictures, though. Please carefully compare their dimensions to your own hardware and see which is a better match.