Patented 1967 Can. Patent No. 3.237.238, however, my part does not match current image found on your web site for this Patent No.
Home was built in 1973. No markings found on actual sliding patio screen door itself.
Please see attached pics (sorry, a bit blurry)
Paul from SWISCO responded:
June 9, 2015
This looks like an old metal version of our 84-020. Check it out and let me know if you could use this as a replacement.