Looking for replacement window balance springs

Question

On the back of the window springs reads ( 23 3 BO Caldwell ). I think I have the correct replacements but would to verify. The metal rail is 24 inches long. The bottom plastic is 1 inch wide.

Bob · Accepted Answer

Hello there. See either our S351-24 or S390-24. The only difference between these two balances is the depth of the bottom nylon shoe, or the measurement from heel to toe. See the diagram below to be safe. If your shoe's depth is 1", then go with the S351-24. In either case, for a stamp option choose 2330.

Comparison of the S351 and S390 balance shoes.