Window spring
Thanks for writing in! The pivot bar you have here in the window channel is no longer made. However, the good news is that we've confirmed our 15-177 will work well as a suitable replacement. Take a look over the dimensions below to confirm that this is the right replacement for your existing coil balance shoe.
These are compatible with the 1/2" thick Series 152 coil balance springs. To determine the correct spring strength for a particular sash, you'll need to look for any stamps/markings on the metal coil(s) in the window.
If there are no stamps/markings or they are hard to read, you'll need to obtain the exact weight of your sash. Once you have the sash weight, you'll divide it by the number of coils in the window to get the spring strength needed to complete each assembly.
You'll need to secure the coil to the shoe using the 33-072 and you may also need the 15-143 coil bushing and the 15-144 coil bushing cap.
