Willys made its first 25,000 MB Jeeps with a welded flat iron “slat” radiator grille. It was Ford who first designed and implemented the now familiar and distinctive stamped, slotted steel grille into its cars, which was lighter, used fewer resources, and was less costly to produce. Along with many other design features innovated by Ford, this was adopted by Willys and implemented into the standard World War II Jeep by April 1942.
Today, Jeep makers proudly retain the automobile’s historical connection to the visage of its predecessors by using a trademarked grille featuring a standard number of vertical openings or ‘slots’. However, in order to be able to get theirs trademarked, Willys gave their post-war jeeps seven slots instead of Ford’s nine-slot design. Through a series of corporate take-overs and mergers, AM General Corporation ended up with the rights to use the seven-slot grille as well, which they in turn extended to Chrysler when it acquired American Motors Corporation, then manufacturer of Jeep, in 1987.
Info from http://en.wikipedia.org/wiki/Willys_MB
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