Window Balance Replacement

Question

Hello,

I'm looking for replacement for my broken balance. The channel is 1/2 wide and 28" in length with stamp B.S.I 27 C. Thank you

Bob · Accepted Answer

Thanks for posting. This looks like either an S351-28 or S390-28 Channel Balance. The only difference between these two balances is the depth of the bottom nylon shoe, or the 'heel-to-toe' measurement. See the diagram below for reference. Compare both balances with your old hardware to see what matches best. In either case, for a new stamp option choose 2730.

Comparison of the S351 and S390 balance shoes.