We faithfully reproduced them from factory blueprints. Blem Products research was to simply try and copy other reproductions. We even intentionally produced a few totally phony air dams for them. In line with their phony research, they even copied those too. Blem Products would not recognize research: "IF THEY STEPPED IN IT, GOT IT ON THEIR SHOE AND IT STUNK LIKE YOU KNOW WHAT" - and you can quote me on this. AVOID WRINKLED PSA They also screwed up on the GM specified SAE grades of rubber, because they never had any blueprints. At cruises and Corvette shows, I have seen the improper grade items. They are easily detected by the large air cells visible in the rubber. Look at any of your originals and you will hardle see the air cells in the rubber.