Series 180 Coil Balance

Hello. Typically there are stamps on the coil springs that indicate the spring weights you should select. If there are none or you're unsure, weigh the window sash these balances support. Give me that exact weight and I can calculate everything for you.

Perfect, thanks. In that case, use the S180-08 8 pound spring, one for each side of the window. That will equal 16 pounds of support overall, which is close enough to the 15.8 pound sash weight to work just fine. Let me know if you have questions.