Leica have announced they are no longer producing this lens 

With its impressive angle of view of 107?, this new TRI-ELMAR conquers 16 mm super wide-angle photography in perfect Leica M style. Due to the minimal distortion and barely perceptible field curvature, it can be recommended for highly demanding architecture photography even at the 16 mm setting. Used on the digital M8, it produces the image effect of a 21 - 28 mm lens, still enabling extreme wide-angle views. The ultra compact shape is achieved by two aspherical elements. A new design of the interior focusing significantly enhances the quality in the close-focus range through an adaption of the floating element principle. Brilliant field depth can therefore be used from a distance of 0.33 m for hyperfocal photography.

This lens is supplied WITHOUT finder.

A telephoto lens of uncompromising quality with apochromatic color correction, the resolution, contrast, and sharpness of the 135 mm APO-TELYT are optimal at all apertures. It also has very little light falloff even at maximum aperture and minimal distortion, resulting in top pro-level performance. This lens can render the finest details clearly and in rich contrast. As the longest focal length in the Leica M system, it's ideal for shooting over long distances and is the perfect completion of any high-class outfit. It permits distinctive landscape shots with typical telephoto effects: the foreground and background are visually compressed. Moreover, it enables frame-filling portraits to be shot from afar, so the subject is undisturbed.