Mercury XM-800.

The Mercury XM-800 is a concept car created by Mercury and first introduced at the 1954 Chicago Auto Show. In newspaper publicity at its 1954 debut, in Chicago and elsewhere, it was presented with its full name, Mercury Monterey MX-800. The XM, or experimental Mercury, "push car" (meaning that it was not drivable) went the 1954 US auto show circuit season. Although it was promoted by Ford as an "advanced design, engineered to go into volume production,” the XM 800 never passed the concept phase.