The photo on the top of this page shows the very first prototype which was placed at Andy Capp's Cavern. There are several versions of this cabinet. Collectors pay some attention to this detail when they really want one of the first arcades made, but this kind of detail does not change the importance of PONG in the videogame history. However, people always wonder how these machines were numbered at the manufacturing plant and most sellers say erratic things about the serial number of their machines. They were encoded to avoid that people guess how many machines were manufactured and sold.
Serials start with two same letters followed by three or four digits.
Meadows PONG, a remake. Maybe copied from Atari PONG, but the board seems to have nothing in common with Atari's one. Another remake, different from Atari. The one on the left is nearly identical to Atari's one. The other one has nothing in common.