Bottom channel shoe help

A quick learner from California says:
I need to replace a pair of window balances. The mfg number stamped on the balance is "25 2 KN Caldwell". I believe that the correct replacement part is either a series 380 or 385. I've attached a couple of photos of the end which makes me uncertain of the correct series.
User submitted picture of bottom channel balance attachment.
Profile picture of Mike
Mike from SWISCO responded:
Thanks for posting your pictures, Mick.

Take a look at the Swisco S380-26, stamp 2520. The shoe measures 1" in width (or height, as shown in your picture above). Measure your current shoe and see if it matches.

Also, please confirm the length of your channel portion only measures 26" in length.
A quick learner from California says:
Thanks for the follow-up. The shoe measures 1", and the channel-only portion measures 26". However, on your S380-26 order page, you ask that one of four options be selected, corresponding to a number stamped on the channel. My channel's do not have any stamped numbers . . . so I'm not sure what to select.
Thanks again,
Profile picture of Donna
Donna from SWISCO responded:
Hi Mick,
In your first post you told us the mfg number stamped on the balance is "25 2 KN Caldwell", with this information we are able to suggest the 2520 stamp option.
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