Window coil balance springs

A handy person from Jacksonville NC says:
540 is what is on the coil. I saw no other identifying marks, numbers, words or letters on the parts or the window. All of the stickers on the windows appear to have been worn or taken off.
Thumbnail of the uploaded file named 3EA8FC85-12F9-471E-A18F-90291BF092E0.jpeg
Thumbnail of the uploaded file named 3D33D3E0-D8FB-4DE2-9834-A04ADE47041E.jpeg
Thumbnail of the uploaded file named 6D2AC4BF-26C6-4FD8-A1DE-784F67112DA1.jpeg
Profile picture of Emily
Emily from SWISCO responded:

Hello!

This looks like an older version of our 15-180, which uses Series 190 coil springs. Compare our dimensions to yours to see if this matches up to your original pivot shoe. If your coil spring is stamped "540", see the S190-540

How to remove window pivot shoes
How to remove window pivot shoes
VIDEO
WATCH >
Anatomy of a tilt window
Anatomy of a tilt window
VIDEO
WATCH >
How to Replace a Triple Coil Balance System
How to Replace a Triple Coil Balance System
VIDEO
WATCH >
Removing a Triple Coil Window Balance
Removing a Triple Coil Window Balance
GUIDE
READ >
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)
Current wait time is 3-4 business days
We promise that one of our experts will personally get back to you as soon as they are able. Thank you very much for your patience and understanding. If your inquiry is time-sensitive, please feel free to reach us at (888) 991-1929 or at help@swisco.com.