Explorer II

The Rolex Explorer II is bound together by a fixed, engraved 24-hour bezel and an extra hand that began as a way to distinguish day from night underground. Across its generations, that practical arrangement evolved into a second-time-zone display, with a choice between leaner vintage proportions and the broader stance of the modern 42mm watches.

The original 1655, introduced in 1971, is immediately recognizable by its orange arrow hand and unusually busy dial, whose additional markers serve the 24-hour scale. Its hour hands move together, so it isn’t a dual-time watch in the later sense. The 16550 brought a 40mm case, sapphire crystal, a more familiar Rolex sports-watch dial, and an independently adjustable local-hour hand. The long-running 16570 continued that format, offering black or white dials; the white-dial version’s black-bordered markers give it a particularly crisp look.

With the 216570, the case grew to 42mm and the large orange arrow returned, paired with caliber 3187. The succeeding 226570 retains those proportions and the black-or-white dial choice, but moves to caliber 3285, with approximately 70 hours of power reserve.