you have to know in general what years the watch was in production. For example, 8 means 2018 not 1998 or 1988 as the Alpinist reference wasn't in production back then. The next digit or letter is the month. 1-9 translates to January - September. October, November, and December are denoted by a O, N, or D, respectively. The rest of the numbers is the serial number of the case.
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