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.

The Macro-Elmar-M 90 mm f/4 can be used as a compact 90 mm telephoto lens or, in combination with the Leica Macro-Adapter-M, for macro shots up to a magnification of 1:2. Either way, the lens provides an incredibly high imaging performance.

Without the adapter, the Leica Macro-Elmar-M 90 mm f/4 is an extremely versatile telephoto lens ? for example, for portraits with shallow depth of field and in travel photography for capturing details in landscapes. For reportage photography, the Leica Macro-Elmar-M 90 mm f/4 allows photographers to capture discreet shots at a greater distance from the subjects. The Leica Macro-Elmar-M 90 mm f/4 is a compact and lightweight alternative to existing Leica M-Lenses of this focal length. When not in use, the lens can be collapsed to save valuable space in the camera bag.

Apochromatic colour correction and an aspherical lens surface are combined for the first time in this lens of this type. Of its five individual elements, two are made of high-refraction glass, while two others feature anomalous partial dispersion. Its brilliance and quality of resolution are exemplary even at full aperture. Light falloff is very low. Its fast aperture, for a 90mm lens, lets you shoot at relatively short exposure times even in dim light, helping to minimise the effects of camera shake, for instance when photographing street scenes from a distance.