The Big Arrow and the Lost Day: Rolex Explorer II 1655 MK4 Freccione, 1973

The year before this Explorer II's case was made, the French speleologist Michel Siffre came up from six months alone in Midnight Cave, Texas, having discovered that without sunlight his body had drifted from a 24 hour day towards a 48 hour one. That is the problem the Rolex Explorer II reference 1655 was built to solve. Its broad orange arrow turns once every twenty four hours against a steel bezel that does not move, and it answers a single question for someone who has lost the sky: is it day or night up there. This 1973 example carries a Mark IV dial, the stubby hand Italian collectors named the Freccione, and a design that has changed very little in more than half a century.

Rolex Before the Explorer II

The 1655 makes sense only against the company that built it, and that company was defined early by one man's idea that a wristwatch should survive real use.

From London to Geneva

Hans Wilsdorf founded Wilsdorf and Davis in London in 1905 and registered the name Rolex in 1908, choosing a word that was easy to pronounce in any language and short enough to fit on a dial. After the First World War, with post war economic conditions working against a London watch business, the company moved to Geneva in 1919. When Wilsdorf's wife died in 1944 he placed his holdings in the Hans Wilsdorf Foundation, a private trust that has owned Rolex since his death in 1960. The company that built this Explorer II in 1973 answered to no shareholders, which goes some way to explaining how a slow selling, narrowly focused tool watch could stay in its catalogue for well over a decade.

The Oyster and the Perpetual

Two inventions made every later Rolex sports watch possible. The Oyster case of 1926 sealed the movement against water and dust with a screw down caseback, bezel and crown, and Rolex proved it publicly the following year when Mercedes Gleitze wore one during her swim across the English Channel. In 1931 the Perpetual rotor followed, a weighted half disc that wound the mainspring with the movement of the wrist. The Oyster Perpetual printed at the top of this 1655 dial is the combination of those two ideas, more than four decades old by 1973.

Tool watches for extreme places

In 1953 Rolex released both the Explorer and the Submariner, and the GMT-Master followed in 1954 and 1955. The company had registered the Explorer name in January 1953, months before Edmund Hillary and Tenzing Norgay reached the summit of Everest, and Monochrome records the Oyster Perpetual reference 6098 that accompanied the expedition as a pre-Explorer. By the start of the 1970s Rolex had a watch for climbers, one for divers and one for pilots. The Explorer II extended that logic below ground.

1971: The Explorer II Reference 1655 Is Born

Rolex introduced the reference 1655 in 1971. Revolution describes it as a specialist tool watch designed for speleologists and potholers who needed to keep track of time underground, or anywhere long stretches of darkness or daylight make the hour on a twelve hour dial ambiguous. Monochrome describes it the same way, as an instrument for cave exploration, and Beyond the Dial places production from 1971 to 1984, with leftover stock sold into 1985.

Why a caver loses the day

Siffre's experiments are the clearest illustration of the problem. In July 1962 he spent around two months 130 metres below the surface of the Scarasson glacier cave in the Maritime Alps with no clock and no daylight. In 1972 he went further, spending six months in Midnight Cave in southern Texas, where without time cues he settled into a 48 hour rather than a 24 hour cycle. NASA, the French Army and the United States government all studied his findings. Those experiments had nothing to do with Rolex, but they describe exactly the disorientation the 1655 was designed around. Four o'clock on a twelve hour dial looks identical before dawn and in the afternoon. After enough hours underground, a caver has no way of knowing which it is.

A fixed bezel and a 24 hour hand

Rolex's solution was a fourth hand that turns once a day and a solid steel bezel engraved with twenty four hours, even numerals written out and odd hours marked with hashes. On the 1655 the 24 hour hand is locked to the main hour hand, so it cannot be offset to show a second time zone. Monochrome is clear that it is a day and night indicator rather than a GMT function. The bezel is fixed because there is nothing to adjust, and Beyond the Dial notes that a fixed steel bezel was unique to the Explorer II among Rolex sports watches of the period. The GMT-Master 1675 beside it in the catalogue turned its bezel to track another zone. The 1655 tracked only whether the sun was up.

Freccione: The Big Orange Arrow

The hand is the reason this watch has its nickname. Italian collectors called the 1655 the Freccione, meaning big arrow, after the broad orange 24 hour hand that dominates the dial, a naming recorded by Italian Watch Spotter. Beyond the Dial notes that the hand is stubby by design so that it can carry more tritium, which keeps it legible for longer in the dark. It is the only coloured element on a matte black dial, so the eye finds it before anything else, and that order of reading is exactly what a caver needed.

The Steve McQueen myth

The 1655 is also widely called the Steve McQueen Rolex, a name that has no basis in fact. Bob's Watches and Craft and Tailored both state plainly that McQueen never owned or wore one, and Revolution points out that the watch he was photographed wearing was a Submariner reference 5512. The nickname has stuck regardless, but the 1655 never needed a film star. Revolution records that its reception in 1971 was muted, with many finding the dial crowded and the look unappealing. It stayed in production because Rolex believed in what it did.

Calibre 1575 GMT: The Movement Inside

The 1655 runs on the Rolex calibre 1575 in its GMT form, the version that drives the additional 24 hour hand. Millenary Watches dates the 1575 family from 1965 to 1981 and records 25 jewels, a beat of 19,800 vibrations per hour and a power reserve of around 48 hours, with Microstella screws on the balance for fine regulation and hacking seconds that stop the sweep hand when the crown is pulled. Early 1655 movements are also documented stamped 1570, a quirk Monochrome and Craft and Tailored both record.

The beat rate is something you can see. At 19,800 vibrations per hour the seconds hand ticks five and a half times each second, a visibly gentler sweep than the eight steps per second of Rolex's later 28,800 vibration calibres. The same movement family powered the Submariner and Sea-Dweller of the era, and Beyond the Dial notes the architecture is shared with the GMT-Master, which placed the Explorer II squarely inside Rolex's professional line rather than at its edge.

Reading the 1655 MK4 Dial

The 1655 was revised quietly throughout its life. Italian Watch Spotter documents five production dial marks made by the dial maker Stern and two later service dials, alongside four bezel variants, and the seconds hand changed from a plain straight hand on the earliest watches to one carrying a luminous dot, the lollipop. Hairspring estimates the straight hand Mark I was made for around two years.

What makes a Mark IV

The Mark IV is identified by a narrower, taller coronet than the dials before it and by the text at six o'clock, which reads T SWISS < 25 T. That marking declared that the dial's tritium content fell below a regulated limit of 25 millicuries. It was a compliance statement rather than decoration, and it is one of the clearest dial level markers of the reference's progress through the 1970s. Mark numbering itself is a convention settled by dealers and authors rather than by Rolex, sources draw some boundaries differently, and dials were fitted from stock rather than in strict date order, so marks and case years overlap rather than lock together.

Tritium after five decades

Beyond the Dial counts around thirty five tritium plots across the dial and hands of a 1655. Tritium has a half life of roughly twelve and a third years, so a dial printed in the 1970s has passed through four of them. Its glow is long gone, and the luminous compound warms in tone as it ages, from white towards cream and beyond. On a matte black dial with a bright orange hand, that aged lume is part of the character of every surviving 1655.

What 1973 Means on This Watch

Rolex engraved the serial between the lugs at six o'clock, and the reset based chart in our Rolex serial numbers guide places 1973 cases from roughly 3,200,000 to the 1974 start at around 3,568,000. A serial dates the case rather than the day it was sold, and on a reference that sold slowly, a 1973 case could easily have waited in a retailer's cabinet for some time.

The year places this watch in the early part of the reference's life, two years after launch and a year after Siffre's Texas experiment. It also places it at the start of the most turbulent period the Swiss watch industry has faced. Quartz watches were arriving, and Rolex itself worked on quartz technology with other Swiss makers during the 1970s. Yet in 1973 Rolex was still building a mechanical steel watch with an acrylic crystal and a 100 metre Oyster case for people who spent their time in caves. Acrylic was a sound choice for that user, because it deforms rather than shatters and can be polished back when scratched.

The case measures around 39 to 40mm depending on the source, in stainless steel with crown guards, and Beyond the Dial records the Oyster bracelet references 9315 and 7836 on the 1655. There was never a gold version and never a dial colour other than black across the whole run.

Final Thoughts

What we love about this 1655 MK4 is how directly it answers a real question. Siffre showed that without sunlight a person can lose track of the day, and Rolex built a watch that keeps it for them: a fat orange arrow, a steel bezel that never turns, and a GMT calibre given the simplest job it ever had. Behind it sit Wilsdorf's Oyster of 1926, the Perpetual rotor of 1931 and the tool watch line that began on Everest in 1953. A 1973 example belongs to the reference's early years, when the Explorer II was still an unfashionable instrument made for people in the dark, and that is still the best way to understand it.

References

1. Monochrome Watches, In-Depth: The History of the Rolex Explorer II: https://monochrome-watches.com/history-rolex-explorer-ii-adventure-watch-gmt-1655-16550-16570-216570-226570-in-depth/

2. Monochrome Watches, In-Depth: The History of the Rolex Explorer: https://monochrome-watches.com/history-rolex-explorer-from-1953-36mm-1016-14270-114270-214270-124270-in-depth-review/

3. Revolution, Tooled Up: The Rolex Explorer II Reference 1655: https://revolutionwatch.com/tooled-rolex-explorer-ii-reference-1655/

4. Beyond the Dial, Collector Guide: The Rolex Explorer II: https://www.beyondthedial.com/post/collector-guide-the-rolex-explorer-ii-all-references-in-detail/

5. Italian Watch Spotter, The Rolex Explorer II Ref. 1655: A Complete Guide: https://italianwatchspotter.com/rolex-ref-1655-a-complete-guide/?lang=en

6. Hairspring, Mk1 Straight Hand 1655 Rolex Explorer II: https://hairspring.com/blogs/finds/mk1-straight-hand-1655-rolex-explorer-ii

7. Millenary Watches, Rolex Caliber 1575 Complete Guide: https://millenarywatches.com/rolex-caliber-1575-complete-guide/

8. Craft and Tailored, 1974 Rolex Explorer II Ref. 1655: https://www.craftandtailored.com/products/1974-rolex-explorer-ii-ref-1655-mk-ii

9. Bob's Watches, Inside the Rolex Explorer II 1655: https://www.bobswatches.com/rolex/explorer/reference-1655-inside-look

10. Wikipedia, Michel Siffre: https://en.wikipedia.org/wiki/Michel_Siffre

11. Wikipedia, Rolex: https://en.wikipedia.org/wiki/Rolex

12. Wikipedia, Tritium: https://en.wikipedia.org/wiki/Tritium

13. Crown Vintage, Rolex Serial Numbers Guide: https://crownvintage.com.au/blogs/vintage-stories/rolex-serial-numbers

• Case in  great condition with honest some wear visible around both sides of the case
• Bracelet in great condition, hairlines visible with light stretch as to be expected with age.
• Watch has passed 5BAR Pressure Test

• Dial in flawless condition
• Hands very good condition