The designation "shark" applied to the FBW Alpenwagen primarily due to the characteristic chrome grille with its vertically arranged teeth, which were reminiscent of a shark's mouth.

This postbus belonged to a new type of vehicle, the so-called front-steerers. In contrast to the snout postbuses, these had a much better use of space. The new design proved to be a great advantage, especially on the narrow roads of the Alpine passes.