27 3 GM CMC 4

Thanks for reaching out! I'm confident we can recommend a replacement for this window balance. Although, to determine the correct replacement match, I'll need to see a photo of the piece connecting the spring and the string in the middle of balance.

Also, the length of the metal channel should be 28" exactly, which is fairly close to what you've confirmed. Please be sure to double check this. and let me know.

Don't hesitate to reach out with any questions you might have.

Thanks for the additional photos! Your balances can be replaced with the S395-28 Channel Balance. You'll need to select the 2730 stamp option.

A pair of these will support a sash weighing 13 to 19lbs.