wrong size balances

Question

I have three windows I need to replace the balances on. I believe they are the wrong size mostly because you put the hook in the opening and the touch the top of the opening around the windows. the ones that are there are marked 26 9 BSI. I sent 1 photo with the stamp and on comparing balance to actual window.

Can you help
Thanks

User submitted photos of a window balance.

Paul · Accepted Answer

Let us have the width and height of the visible glass portion for each sash. Then, we need the overall width and height of the sash, plus its weight. Finally, show me the original balances that came out of each window, with the metal channel length and the spring code stamped on it. I'll try to sort it out if you can clue me in to which balances came out of which windows.