Looking to identify and replace rail and spring for windows

Question

The rail is 5/9" tall and 1/2" wide (when laying down with spring side up). The rail is 34" long (which excludes the plastic pieces that extent past the end of the rail). The rail has 33300 stamped on it.

User submitted photos of a window balance.

Tom · Accepted Answer

Take a look at our S385-34 channel balance, this looks to be a good match. Just make sure the bottom shoe is the same size as yours.