Can you tell me what which parts I need to replace these? They are 22" by 1/2" (a little over 1/2") long and the stamp says 21 12 BSI DN. I have two windows that need these replaced and they are the same balances with the same markings.
Thanks,
Clarissa
Hey Clarissa. This looks like either an S351-22 or S390-22 . The only difference between these two channel balances is the bottom nylon shoe depth, or the 'heel-to-toe' measurement. See the illustration below for reference. Compare both with your old hardware to see what matches best.
You then have to choose a stamp option, which denotes the strength of the balance. Your stamp code of 21-12 is a little unusual. I recommend obtaining the exact window sash weight. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on the shop page. Let me know if you have any questions.
Thank you! In that case, you would want our S390-22 channel balance with a 2170 stamp option. Two balances with this stamp can hold 34 through 37 pounds, so that should be perfect for this application.
I also saw that you posted photos for a different window. Just to help avoid any confusion, I took the liberty of splitting that off from this page and making it its own thread. You will receive a response for that from one of my colleagues shortly.
