Production and sales dates for such rare and
link time-consuming watches can vary greatly, with some not leaving for retail until years after they began production. Looking to 1955, Audemars Piguet evolved the 5516 slightly to offer the first-ever leap-year
link display on a wristwatch. According to AP's exhaustive records,
link nine such models were made in two distinct series, with all examples remaining within the purview of the 5516 reference.
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