Request for Identification of replacement part (sash balance)

A home owner from Mesa, AZ says:
Thank you for the awesome website and help with identifying my replacement part....I await word from you.
User submitted photos of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
Hey, thanks for posting. I've narrowed this down to two possible channel balance Series: either our Series 351 or our Series 390 balances.

Now, as you can see, there is only one difference between these two Series, and that is their bottom shoe. The Series 351 uses the 15-002 while the Series 390 uses the 15-001. I can't quite tell what you have based on your pictures, though. Please carefully compare their dimensions to your own hardware and see which is a better match.
Comparison of 15-001 & 15-002
Comparison of 15-001 & 15-002
A quick learner from Mesa, AZ says:
I was about to place an order but what about the
Stamp Option Sash Weight Range????? I can't see anything on replacement part that matches the numbers on your chart. Thank you again for your help!
Profile picture of Tom
Tom from SWISCO responded:
Usually a stamp of 28 6 corresponds to our 2860 option, but you should weigh your window sash and compare it to the weight rating shown for the 2860 just to make sure it's correct.
How to Replace a Channel Balance Attachment
How to Replace a Channel Balance Attachment
VIDEO
WATCH >
Classifying Channel Balance Fittings
Classifying Channel Balance Fittings
GUIDE
READ >
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