29" window balance

Question

I have a 29" metal channel on my window balance. I do not see any markings. I am going to replace both balances.

After looking closer, I see a stamp that says 28B.

Paul · Accepted Answer

After looking over all of your photos and information, we believe you should be able to use the S380-29 channel balance in place of your current one. Look it over and see what you think. Your stamping of "28B" would correspond to the 2820 option.