This rack window operator works on Hehr 2400 series Lite-Aire (wide louver) windows and the Hehr 2700 series jalousie windows. They are found on many vintage trailers from the late 1950s through 1970s.
You will need the included link for most applications, but not for single pane Hehr 2400 series windows.
The rack is reversible, and in some cases must be turned upside down, as in the case with Hehr 2700 series windows with two opening panes only.
The swivel handle is sold separately.
See the dimensional drawing for details to see if this operator will work with your window.