Alvin Gottlieb tells us that his father's attitude changed upon playing 'Flipper':

After he played Wayne’s first finished production model, he decided to try to get it approved in some foreign markets where a "Free Play" was considered a "Thing of Value" that made it a part of gambling. Suren Fesjian’s Mondial Company managed to get it approved in France and Italy, and the rest is history.

Gottlieb's changeover from cabinets having wood side rails and square backboxes to cabinets having metal side rails and wedge head backboxes occurred during production of this game. Reportedly, the first 415 units were manufactured as woodrails and the remaining 685 units as wedge heads. These numbers have not been confirmed to us. Included in this listing are two examples of this woodrail cabinet. One is marked 'Sample Game' because of its serial number while the other is marked 'Early Production' because we do not know its serial number. The Sample game has cabinet art that was not used on the production games, nor have we seen it in any other production run in a search of years 1950-1965. A close comparison showed up in the lower cabinet art of Gottlieb's 1963 'Square Head'.

The woodrail version was the last game to have Gottlieb's famous phrase on the backglass: Amusement Pinballs, as American as Baseball and Hot Dogs! The first game to have it was Gottlieb's 1955 'Marathon'. The phrase did not appear on the wedgehead version nor on later games.

Wayne Neyens tells us why Gottlieb began using the wedge head design:

When the flipper games came on location we soon heard complaints about side by side games. It was hard to keep the games in line and separated so that there was room for two pairs of hands. Well the four player solved the problem, the lite box did the job of separation. The answer became obvious, we needed to increase the size of the lite box on single player games. I believe that Doc [Roman F. "Doc" Garbark, head of mechanical engineering at Gottlieb] came up with the WEDGE HEAD design. It was cheaper for us to spend a little more money on the cabinet than to buy a larger glass, more art work, and screens, etc. Also, it was a new look, a win win deal for us. I don't know who hung the name WEDGE HEAD on the design but it is very descriptive.

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