Vinyl Window Parts

A handy person from San Francisco says:
This window part is from a Superior Window co. vinyl window. This California company has since been closed. This part helps the sash stay open and I believe its called a balance. Without this part which goes on both the right or left side of the sash the window slams down and won't stay open.
The sash is 26 1/4" x 22 1/2" and weighs 10 lbs.
User submitted photos of window hardware.
Profile picture of Paul
Paul from SWISCO responded:
The nylon fitting looks like our 15-102 , and the coil spring, we believe, is S145-5 . Please compare and see if your spring number matches; it should be labeled with a 5, if I identified the coil correctly.
How to Replace a Triple Coil Balance System
How to Replace a Triple Coil Balance System
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