Here is an advertisement for the Heuer "Chess Champion" . . .

Based on the language of the advertisement, indicating that this is a "new product", this must have been the first version of the clock, with plastic plungers. The later version of the clock (as shown on Hodinkee) used aluminum plungers.

Jeff

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: Here's a nice posting by Jack Forster, on Hodinkee, about chess
: and chess clocks --
: https://www.hodinkee.com/articles/queens-gambit-netflix-chess-clocks

: The Netflix series, The Queen's Gambit, has created enormous
: interest in chess, and chess clocks, as well.

: As with so many other types of sports timing, Heuer seems to have
: held a dominant position in the market, in the 1960s.

: Jeff

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