I am trying to find parts to fix the two windows in the pictures. Both are 36" window. When you tilt out the top window to clean, one side comes lose. It is a spring and white cable tension system. A rod goes through the spring and connects to a blue piece on the bottom. For the other window, the complete system is missing on one side.
Bob from SWISCO responded:
November 4, 2019
Thanks for writing in. This looks like an old crossbow balance. These aren't made anymore, but they can be replaced with our Series 795 Channel Balances. See the video below for details.