Unknown Coil Balance

Question

Only marking on balance appears to be the letter "A" stamped on the back of one of the parts.
Window sash is 31" wide by 33.5" tall and weighs 20.1 lbs (weighed it with luggage scale).

User submitted photos of a window balance.

Paul · Accepted Answer

Based on your photos, it seems like your pivot shoe has broken. That may be all you need to replace. See our 15-180, this looks like a good match. I've also related other parts you may be interested in, but you only need to replace what's broken.