The 4-stop, 95mm Tiffen Coarse Combination 85/ND Filter is a combination of both an amber color conversion 85 and a 1.2 neutral density filter. There is a 1.2 density for darkening of the entire image in order to photograph with a wider aperture or slower shutter speed than normally required. The 85 filtration covers the entire filter plane and converts the color temperature to 3400K for use with type A (tungsten) films.
The 1.2 ND filter provides a reduction of 4 stops. This filter is constructed from Water White glass and is made using ColorCore technology, a process that involves laminating the filter substrate between two pieces of optical glass, grinding flat to a tolerance of 10,000th of an inch, and then mounting to precision metal rings. This filter has a diameter of 95mm with coarse threads.