Widow Balancers

Hello,

It looks like you have either our S351, with a 15-002 bottom attachment, or S390, with a 15-001 bottom attachment. Take a look at the image below to determine which balance you'll need. You'll also need to locate the stamps on both metal channels to choose the corresponding spring strength options for your replacement balances. Thank you!

Comparison of the S351 and S390 balance shoes.

Once you choose between the S351 and S390 by following the diagram I sent you, you'll use a 1640 strength option for your 17" balance and a 2230 strength option for the 23" balance.