A past question from NO QUARTZ, the free daily watch quiz. The answer is highlighted below.

Grand Complication (bonus)·Multiple choice

The Sea-Dweller launched in 1967 rated to 610 m. In what year did Rolex double that rating to 1,220 m?

  • A.1971
  • B.1978Correct answer
  • C.1983
  • D.1989

The story behind it

The 1978 ref. 16660, the 'Triple Six', doubled the Sea-Dweller's rating from 2,000 ft to 4,000 ft (1,220 m). It also replaced the acrylic crystal with sapphire and fitted a larger helium escape valve to go with the higher rating. The figure has lasted: the current 43 mm Sea-Dweller 126600 is still rated to exactly 1,220 m, almost five decades later.

From NO QUARTZ Ref. NQ0002, the puzzle for Sept 24, 2026. It was that day's Grand Complication, a harder bonus question for players who scored 80 or more.

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