422c

Hello,

It looks like you have either our S351-23, with a 15-002 bottom attachment, or S390-23, with a 15-001 bottom attachment. Take a look at the image below to determine which balance you'll need. 

You'll also need a 2230 spring strength option for your replacement balances if the originals are stamped with 22C. Thank you!

Comparison of the S351 and S390 balance shoes.