[Leica] A42 M Polarizer #13351 fits many other brands

[leica at screengang.com (Didier Ludwig)]

Just noticed that the #13351 Leica Polarizer also fits on the Helios-103 
1.8/50 (Contax-mount), Petri Color 35 (though causing heavy finder 
intrusion), and likely many other lenses with 40.5mm filter thread. The 
Jupiter-3 aperture ring gets almost blocked (but who uses this lens other 
than wide open?:-) With the LTM 2/35 Canon (40mm filter size), the aperture 
ring is movable but a bit difficult to handle. Even the 28mm Color Skopar 
takes it (recommended for use on R-D1 only because of vignetting), I can 
assume the 35 classic and 50 Skopars also take it. 
Didier