The Dodge Charger 500 was produced by Dodge as a result of not winning NASCAR in 1968, being defeated by Ford and Chevrolet. Tunnel tests indicated that the indented grill of the '68 Charger caused drag, and the recessed backlight rendered the car unstable on oval racetracks. To fix these aerodynamic issues, Dodge installed a flush grill and headlights from a '68 Coronet and made the backlight flush by mounting a large rear window to fill the "vacuum" left by the '68 backlight. This greatly improved aerodynamics.
This casting is very similar to the '69 Dodge Charger casting released by Hot wheels in 2004.