Window Balances - 36 B BSI & 35 C BSI

A quick learner from Jersey City, NJ says:
I have two different types of balances that I need to replace and I am having a tough time identifying them.

What I do know:

Balance A

Width: 9/16"
Depth: 5/8"
Channel Length: 37"
Stamped on end: 36 B B.S.I.
User submitted photo of their 36 B B.S.I. channel balance.

Balance B

Width: 9/16"
Depth: 5/8"
Channel Length: 36"
Stamped on end: 35 C
User submitted photos of their 35 C B,S,I. channel balance.
If you could help me find the exact balance I need to get to repalce these I would appreciate it.

David H.
Profile picture of Donna
Donna from SWISCO responded:
The shoe of your "Balance B" is broken but if it is the same as the your "Balance A", they are both Series 390.

37" 36B Choose S390-27 with the 3620 stamp option

36" 35C Choose S390-36 with the 3530 stamp option
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