Shallow lens hood designed for a Leica Summicron 35mm F2 lens. The hood protrudes just 10mm ahead of the lens filter thread. It can be used with or without a standard 39mm filter mounted. The 42mm outer dimension of the lens front is gripped tightly by the flexible plastic of the hood. The square opening maximizes the shading of the front element while minimizing viewfinder blockage. This hood will provide close or equal shading to the original hood. There are two aperture markers, one centered for M-mount lenses, and one off center for Leica screw mount lenses. This hood will also fit a Canon 35mm F2 LTM with a 40mm filter mounted. NOTE: This hood attaches with friction, and will initially be very tight fitting. The grip pads can be gently scraped with a blade, to get a perfect fit. If after frequently taking it on and off, the fit becomes loose, some rubber cement can be dotted to the grip pads. Let it dry, and it will grip nicely again.