I have need for replacement counter balances on my Jordan windows non tilt. They all appear to have the same counter balance of 9/16" wide and the metal part is 28" long.
The only numbers I can find are 27 9 and then CV horizontal stamp and then BSI vertical. The weights of the windows range from 27.6 pounds to 27.9 pounds. It looks similar to the S351 on your site.
Any assistance will be greatly appreciated. Or If I need to provide more information. Thank You.