Side channel balance

Thanks for writing in. This looks like either an S380-29 or S385-29 to me. The only difference between these two balances is the depth of the bottom nylon shoe, or the 'heel-to-toe' measurement, so compare both with your old hardware to see what matches best. The picture below illustrates this difference. In either case, you'll need a stamp option of 2820.

Comparison of the S378, S380 and S385 balance shoes.