Oil filter bolt... what’s up with this?

Looks like slag from the mill when it was made, Bolts are made from wire, My friend worked at a pickling plant that got the coils of wire from the mill in Cleveland and they put them in the acid tank to pickle them then they went in the oven to get annealed so they could make bolts out of them. They didn't pickle the wire or leave it in long enough, I would not use it!