Other than in an SLR, where the user sees his subject looking through the lens, the effect of a polarizing filter cannot be judged in the viewfinder of a rangefinder camera. Nevertheless, many users of rangefinder cameras would like to benefit from the photographic advantages of a polarizing filter, such as higher color saturation and reduction of reflections at non-metallic surfaces. A very easy-to-handle universal polarizing filter solves this problem for LEICA M-photographers.

A hinge allows it to be swung exactly 180° over the viewfinder for composition and setting, and back again over the lens for metering and shooting. The two special adapters (threaded rings) for the filter sizes E 39 and E 46 delivered with the filter enable the use of the majority of the present interchangeable lenses for the LEICA M6-models; others for earlier lenses are also available. The new universal polarizing filter replaces the former polarizing filter A42.