Bracelet codes are stamped inside the clasp.
link In these early years, a batch and production year were also stamped on the clasp. In the '70s, Rolex began using a system where a letter represented the year, and the number
link represented the month. You can
link find a number of these code tables on the Internet, but look at this one from Bob's Watches, for example, and you can tell that a bracelet stamped "G6" dates to June 1982.
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