Balance Spring

Question

I have a Caldwell non-tilt window balance spring that needs to be replaced. It is marked as 25 4 FO CALDWELL. It is a 1/2" wide channel with a 26" length. It appears to be a 19-005 top and a 15-004 shoe (1 3/32" width). Am I correct that this would be a 26" S385 series balance spring and can you confirm that it would correspond to the CALDWELL numbers?

Thanks.
Greg

Tom · Accepted Answer

A 26" long, 1/2" wide channel balance with a 19-005 top and a 15-004 shoe would be our S385-26. The 1-3/32" makes sense for a 15-004 shoe. For a stamp of "25 4," you should select a 2540 stamp option.