Replacement Part

Question

I am trying to find the replacement part for a window pictured here. The letters and numbers read 21 B B.S.I.

Any assistance you could give would be greatly appreciated. If you have this replacement part, please include what the price would be.

Thanks you,
Susan

Casey · Accepted Answer

Hi Susan,

It looks like you have either our S351-22, with a 15-002 bottom attachment, or S390-22, 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 2120 spring strength option for your replacement balances. Thank you!

Comparison of the S351 and S390 balance shoes.