Every Seiko diver descends from this one. The 62MAS arrived in 1965 as the company's first purpose-built diver: 150 meters, caliber 6217, a modest 37 mm case, and the start of a succession chain that runs unbroken to the SKX and beyond. Whether its design owes anything to the Swiss divers of the day is a debate collectors have never settled; what is settled is that Seiko never stopped iterating on it.
The production window is short and, honestly, approximate: 1965 until 1967 or 1968 depending on which records you trust, and Seiko's own archive does not settle it. That brevity plus sixty years of tropical wrists means honest examples are scarce, and the reference has become the blue chip of the vintage Seiko world, reissued by Seiko itself repeatedly, which tells you what the company thinks of it.
The founder's file. Original dials and bezel inserts are the whole value: a relumed dial or swapped insert takes a serious watch down to a parts price. At 37 mm it wears smaller than everything that followed, which surprises buyers raised on Turtles. Budget for the honest example, not the shiny one.
Production windows and specifications compiled from documented collector references and period catalogs, cross-checked across independent sources; manufacturer records for this era are approximate by Seiko's own account.