Oil fill cap ID

[Rixls6]

Found this chrome oil fill cap that is very similar to the ones used originally on the `69 and `70 big blocks, but the center rivet is square-headed rather than rounded, and has no "S".
Does anyone know what it would have been originally for?

http://i36.photobucket.com/albums/e43/Rixls6/oilcaps001.jpg

http://i36.photobucket.com/albums/e43/Rixls6/oilcaps002.jpg

[Postsedan]

Rick,

Sure, These are reproduced by none other than....

Sponge Bob Square Pants, LOL!

http://img.photobucket.com/albums/v677/Postsedan/Postsedan2011/99-2.gif

Dan

[Postsedan]

Rick,

Show a pic of the back side....if not someone might think this was done as a repair?

Dan

[SuperNovaSS]

I have a few of those on original chrome covers as well.

Jason

[Salvatore]

prolly just a different supplier.

[Plowman]

Later 1980 or so GM with oil sticker on top of square-headed.