non tilt window balance

 Thanks for your post! I was able to narrow down the replacement balances to a few possible replacements, but I'll just need to photo to be sure of the correct recommendation. Please provide a clear photo of the bracket in the center of the balance, this is where the spring and the string meets in the middle.

You'll also need to confirm the measurement for the depth (front to back) of your bottom shoe. Take a look at the diagram below for reference.

Profile view of a winged balance attachment

Thanks for the additional photos. Your balances can be replaced with either the S380-28 with a 1" shoe or the S385-28 with a 1-3/32" shoe. To confirm which of these is the correct replacement, you'll need to confirm the depth of the shoe, as mentioned. Here's a better diagram to use as a reference.

Comparison of the S378, S380 and S385 balance shoes.