Replacement of channel balances

Hello there. This channel balance looks like it is 1/2" wide. Therefore I think you have either the S380-26 or S385-26. The only difference between these two balances is the 'depth' of the bottom nylon shoe, or the heel-to-measurement. See the diagram below for reference. Measure your old balance's shoe to see what matches best. For a stamp option choose 2530.

Comparison of the S378, S380 and S385 balance shoes.