4×5.65 Clear Glass Filter

Ah the classic Black Promist filter.  Also known as Supermist Black.  Also know as Black Mist Diffusion.  Also know as… look, there have been dozens of versions of the same thing under different names over the last x decades.  If you’re looking for any of the above names, this is what you’re looking for.  Not to be confused with mist type filters that don’t say “black”.  Those are different.