Window balancers

A home owner from Redding, CA says:
I have a window balancer block and tacle type the number on the balancer is: 31 9 cv cmc 2

The metal bar is 1/2" and measures 32" long

Would it still be a series S385-32. I do not know what the options mean on the s385 block and tackle balances.
User submitted photo of their balance attachments.
Profile picture of Paul
Paul from SWISCO responded:
Yes, you are correct. You have S385-32, but I need the weight of sash to confirm which option you need to choose. Remove the window sash from the frame and weight it on a scale (such as a bathroom scale).
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