For bay window. The only identifier on the window balance says 17 3 BO Caldwell.
It is 18 in long. 5/8" deep. What is the replacement series number?
Bob from SWISCO responded:
September 6, 2019
Thanks for writing in. See our S380-18 or S385-18. The only difference between these two balances is the 'depth' of the bottom nylon shoe, so compare both with your old balance to see what matches best. You will need a stamp option of 1730.