Need model number for non tilting window balance

Hello,

We'd be happy to help but we will need to see photos of the top and bottom balance fittings of a balance fully removed from the window to narrow down your replacement options. Thank you! 

Thanks for getting back to us. It looks like you have either our S351-12, with a 15-002 bottom attachment, or S390-12, 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 1120 spring strength option for your replacement balances. Thank you!

Comparison of the S351 and S390 balance shoes.