Replaement Window Balance

A handy person from Winter Springs Florida says:
I have a non-tilting windows that has a channel balancer that is 30" long and 1/2" wide. From the picture it most resembles the series 380 and the series 385 channel balancer.

I attached 2 pictures of the channel balancer I removed from the window.

Any help in choosing the correct channel balancer would be greatly appreciated.
A customer submitted photo of a window balance.
Profile picture of Mike
Mike from SWISCO responded:
Thanks for posting.

Could you please supply us with the measurements of the bottom attachment, as well as the stamp number?
A handy person from Winter Springs, FL says:
The Stamp number is 28C USB
Profile picture of Paul
Paul from SWISCO responded:
Please take a look at our S385-29 Channel Balance with the 2830 option.
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)
Current wait time is 4-7 business days
We promise that one of our experts will personally get back to you as soon as they are able. Thank you very much for your patience and understanding. If your inquiry is time-sensitive, please feel free to reach us at 856-317-6263 or at