Kodak Polymax Poly Contrast Filter Kit, 3.5" Individual Filters for Above the Lens Use.

KODAK POLYMAX Filter Kit - Controls the contrast of Kodak selective-contrast papers. Intended to be used above the lens. Provides an expanded range of filter contrast grades from approximately Grade -1 to Grade 5+. Filter 2 is considered "normal" and provides the contrast of a typical white-light exposure. Each set includes -1, 0, 1/2, 1, 1 1/2, 2, 2 1/2, 3, 3 1/2, 4, 4 1/2, 5+.