[Unclenick]

Brownells Oxynate 84. It is for bluing stainless and cast iron. But it is a hot bluing method, so you need to be equipped for hot bluing to use it.

I've got a gallon of cold black for stainless, but a kind of charcoal gray is all I ever get out of it. Abrasive blasting helps, but on polished stainless it is pretty disappointing. I got it for coloring screws to match a panel originally, but wasn't pleased by the results.