Coil balances replacement

A home owner from Maryland says:
My windows are Capital 9555 series vinyl double hung windows with a measure in 31"x31" as shown in the attached files. The coil width is 0.5".
Need your help to determine the type of the coil.

Thanks!
User submitted photos of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
Your pivot shoe looks like our 15-180, which is commonly used with the Series 190 coil spring. See what you think.
A quick learner from Maryland says:
Thanks for the help! I thought it'd be S190 coil spring as well, though not entirely sure which type of S190 coil I should pick from the selections of 440,540,640,740,840. The number code on my coil is 7 as you can see in the 2nd image. Does that indicate I should choose S190-740?

Thanks again!
Profile picture of Tom
Tom from SWISCO responded:
Yes, if the number on your old spring reads "7" then our S190-740 would be the best option. Each of these springs is rated to hold 7 pounds, so if you have two springs altogether then they are meant to hold a 14 pound sash. If you have four springs altogether, they're meant to hold a 28 pound sash, and so on. You can always weigh your sash on a scale to confirm that these are correct.
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