Balance Spring

Question

This is a 22" unit. The numbers on it are '21 2 IT CMC 4'.We will need to order two of these.Thank you for your assistance.

Bob · Accepted Answer

Thanks for posting. This looks like either an S351-22 or S390-22 Channel Balance. The only difference between these two balances is the depth of the bottom nylon shoe, or the 'heel-to-toe' measurement. See the diagram below for reference. Compare both with your old hardware to see what matches best. For a stamp option choose, 2120.

Comparison of the S351 and S390 balance shoes.