Proper size of spiral spring

Question

The spiral spring on my tilt in window is bad. It's 5/8 inch across and the length measured from the end where the screw holds it the beginning of blue tip is 28 3/8 inches. I' need to know which spring will meet my needs- the 28" or 29" ? Thank you for helping me out.
Pete

Paul · Accepted Answer

Based on your current size, I recommend going with our S600-28 spiral balance, with a Blue Tip, of course.