Any Idea what these marks mean? A-C 375 and Triangle Symbol

by Stephen
(California, USA)

Marks on Underside of Clasp

I've got a nice Gold Bracelet that I'm trying to find more info about. I've uploaded an image of the Marks on the bottom of the Clasp. There are marks on 4 different places, but they are all the same with the exception of the symbols.

It is also a very unique link that I'm unable to find anywhere. A couple of jewelers told me that they thought it may be one of a kind. Or, maybe it's Walmart Jewelry? ;) I have no idea.

Any help would be greatly appreciated.

Thank you!