Rolex Explorer II
The Explorer II is the fixed-bezel 24-hour sibling to the Explorer I. Rolex introduced it in 1971 for low-light and remote-field use, and every Explorer II has kept the 24-hour hand and engraved bezel.
The line runs from the 1655, whose 24-hour hand is linked to local time, through the independently adjustable 16550, 16570, and 216570, to the current 226570.
Common entry points
The first Explorer II (1971–1984)
| Reference | Production | Movement | Case | Key distinction |
|---|---|---|---|---|
| 1655 | 1971–1984 | Cal. 1575 GMT | 40mm SS, acrylic | Orange 24-hour hand; documented Mark and service-dial groups; linked-hand 24-hour display; fixed engraved steel bezel |
The transitional reference (1985–1989)
| Reference | Production | Movement | Case | Key distinction |
|---|---|---|---|---|
| 16550 | 1985–1989 | Cal. 3085 | 40mm SS, sapphire | First sapphire and first independent-hour GMT; black or white dial; documented cream and rail-dial variants |
The long-run modern reference (1989–2010)
| Reference | Production | Movement | Case | Key distinction |
|---|---|---|---|---|
| 16570 | 1989–2010 | Cal. 3185, then 3186 late | 40mm SS, sapphire | Tritium, Luminova, and Super-LumiNova dial eras; late 3186 examples; black or white dial; documented military issue |
Current-production successors
The 42 mm successors continue the line beyond the vintage and neo-vintage generations. Both keep the engraved solid-steel 24-hour bezel used since 1971; Explorer II references have not adopted a Cerachrom insert.
- 216570 (2011–2021) — 42mm case, cal. 3187, reintroduced orange 24-hour hand
- 226570 (2021–present) — cal. 3285, current production
Movement progression
| Caliber | Frequency | Power reserve | 24-hour function | Used in | Notes |
|---|---|---|---|---|---|
| 1575 GMT | 19,800 vph | ~48 hr | linked to hour hand | 1655 | Shared with GMT-Master 1675; 24-hour hand advances with hour hand, works as day-night indicator |
| 3085 | 28,800 vph | catalogues vary, about 42–48 hr | independent-hour | 16550 | First Explorer II with independent-hour GMT; also used in GMT-Master II 16760 |
| 3185 | 28,800 vph | ~50 hr | independent-hour | 16570 | Successor to 3085 with minor revisions; ran through most of the 16570 |
| 3186 | 28,800 vph | ~50 hr | independent-hour | 16570 (late run) | Revised gear train and blue Parachrom hairspring |
Dial variant highlights
Variant taxonomy across the line, in brief:
- 1655 Mark dials: collector groups commonly called Mk1 through Mk5, plus documented Beyeler service dials. Names and boundaries vary between sources.
- 16550 cream / rail dial: some Polar dials aged to cream; the rail variant aligns the C of CHRONOMETER over the C of CERTIFIED.
- 16570 Swiss-only: a short Luminova period around 1998–1999 retained SWISS rather than SWISS MADE printing. Its share of total production is not established.
Cross-references
The Explorer II is the sibling of the Explorer I line and shares calibers and case architecture with the GMT-Master line. Caliber 1575 in the 1655 is the same movement fitted to the GMT-Master 1675, configured differently: linked-hand on the Explorer II, independent-hour on the GMT-Master. The 16550's caliber 3085 is the movement that also powered the GMT-Master II 16760.
Related families
- Explorer — the original line. Same case lineage, same Mercedes hands, no 24-hour function.
- GMT-Master — the shared-movement sibling. Caliber 1575 GMT in the 1655 and caliber 3085 in the 16550 carry over from the GMT-Master family.
- Submariner — the parallel tool line. Same case-era cadence, same generation-by-generation movement progression.
- Serial numbers by year — date any Explorer II from its serial
- Movement reference — the calibers used across the Explorer II line
- Bracelet & clasp guide — bracelet types, end-links, and clasp date codes
Sources
- In-Depth: The History of the Rolex Explorer II, The Ultimate Adventure Watch — Monochrome
- Tooled Up: The Rolex Explorer II Reference 1655 — Ross Povey, Revolution
- Mr Rolex Orange Hand, Reinhold Messner and Sir Edmund Hillary's Original Vintage Explorer II ref 1655 — Philipp Stahl, Rolex Passion Report
- Spelunking Into the Details: The Rolex Explorer II Reference 16550 — Tony Traina, European Watch Co.
- Buyer's Guide: Explorer II Ref. 16570, All Variations — Jorg Weppelink, Fratello
- The Rolex Explorer II Ref. 1655: A Complete Guide — Andrea David, Italian Watch Spotter
- Rolex Explorer II 16550 vs 16570 — Alessandro Metelli, Italian Watch Spotter
- Exceptional Movements In History: Rolex Caliber 1575 — Quill & Pad
- Rolex Caliber 3085 Complete Guide — Millenary Watches
- Collector Guide: The Rolex Explorer II — All References in Detail — Beyond The Dial
- The Vintage Rolex Field Manual — Colin A. White, Morning Tundra