Non tilt window channel balances needed

Question

Stamp reads 29-2 bsi. Channel measures 1/2", metal measures 30", bottom winged shoe measures 1". Window measures 23 1/2"x 32 1/2". Pictures included are for this window only.
Resembles your part S380?
2nd Window measures 32 1/2" x 50 1/2; stamped 2990-38 bsi... I don't have channel balances out for this window, but assuming it is similar to above 1st window.
Please advise replacement parts required?

Casey · Accepted Answer

Hello,

Your balance with the 29-2 stamp does appear to match our S380-30 with a 2920 spring strength option.

Your other window should also use the S380-30 balance but you can compare the top and bottom nylon attachments to confirm. Your second stamp number is based on an outdated weight system, so your best bet would be to remove and weigh your window sash and choose your spring strength option based on the chart under the product description on our website. Thank you!