The 1968 C-body and prior (back until about 1963?) had a curved "aero" attachment to the blade assy. Put extra downforce on the blade for better "at speed" wiping performance. Silver, but not really shiny silver. Seems like the inserts had a red "button" sticking through a hole in the blade assy body?
1969 model year and later had the "normal" blades, sans aerofoil.
Enjoy!
CBODY67