Source: https://myreversostory.com/calibres Summary: Around fifty calibres built for the Jaeger-LeCoultre Reverso since 1931, from the Tavannes 064 to the Gyrotourbillon, the Quadriptyque and cal. 953. Updated: 2026-10-29 Publisher: My Reverso Story (https://myreversostory.com), an independent collector archive, not affiliated with Jaeger-LeCoultre. The Calibres # The wrong shape for everything. Watchmaking is built around the circle. Gear trains are round, balance wheels are round, repeater gongs want to be coiled circles. The Reverso is a rectangle that turns over — and the fifty-odd movements built to live inside it are the record of what happens when a house refuses to accept that as a limitation. Fifty Movements, One Problem Since 1931, Jaeger-LeCoultre has created around fifty different calibres for the Reverso alone — from the smallest mechanisms it makes to some of the most complicated, each one moulded to the shape of a watch that has to work upside down and back to front. What follows is not a spec sheet. It is the order in which the problems were solved. I 1931 – 1933  ·  2 calibres ## Borrowed Time For its first two years the most famous rectangular watch in the world ran on somebody else’s movement. ### Tavannes cal. 064 1931–1933 Manual · rectangular · bought-in Reverso first series; Reverso De Luxe The Reverso began life powered by a competitor, and the contract shows it was planned that way: Article 14 of the 1931 agreement expressly allowed movements from Tavannes, Movado or Jaeger/LeCoultre, while stating that a special movement “completely suited” to Chauvot’s case would follow. It had to. LeCoultre’s round calibres were too small for the rectangle and the Duoplan, its own finest shaped movement and the obvious candidate, was too thick. So Tavannes *calibre 064* ran in the gentlemen’s watches and *calibre 050* in the smaller ladies’ model, both without seconds, until about the end of 1932. Fritz calls it the one moment in the manufacture’s history when the maker of fine movements *par excellence* lacked the right calibre for its own watch. ### The Duoplan (why nothing fitted) 1925 Two-storey architecture · large balance in a small movement Not a Reverso calibre — the reason the Reverso needed Tavannes The movement that explains the Reverso’s awkward first two years. Devised by Henri Rodanet, Jaeger’s technical director in Paris, and industrialised by LeCoultre at Le Sentier, the Duoplan stacked the movement across two levels (barrel and wheel train below, balance on the tier above), freeing space for a balance wheel far larger than a small movement could otherwise carry, and with it a precision nobody had managed at that size. It was radical, celebrated, and far too thick for Chauvot’s sliding case. So the watch that prefigured the Reverso’s spirit of rethinking received wisdom was the very movement that could not go inside it. II 1933 – 1948  ·  4 calibres ## The House Rectangles Eleven different movements powered the pre-war Reverso. These are the ones that mattered. ### LeCoultre cal. 11U / 410 from 1933 Manual · 15 jewels · 18,000 vph · ~50 h Reverso with subsidiary seconds at 6 The movement the 1931 contract had promised: one “completely suited” to Chauvot’s case. Two years from problem to production movement is fast, which tells you how quickly the watch had succeeded, and it marked LeCoultre’s breakthrough, after almost a century as a barely-known maker of fine movements, into selling complete watches under its own name. Collectors can date a vintage Reverso quite precisely from the many small changes made to the calibre 11 family over the years. The modern cal. 822 was drawn, six decades later, to look deliberately like this one. ### Cal. 413 1937 Manual · small seconds Reverso 1937 small seconds The manufacture’s fourth in-house Reverso movement, and a useful dating tool: watches carrying it have black dials signed *Jaeger-LeCoultre* (the first year the merged name appeared), which pins them precisely to 1937. ### LeCoultre cal. 411 from 1933 Manual · centre seconds Reverso with sweeping centre seconds The 410’s twin, released simultaneously with a sweeping centre seconds hand instead of a subsidiary dial. Many variants followed; eleven distinct movements powered the Reverso before production stopped in the late 1940s. ### Cal. 437/1 and P437/1 c.1947 Manual · centre seconds Reverso “Interchangeable / Reversible” The pair fitted to the late-1940s two-part-case Reverso, a little-documented variant in pink gold and steel with a centre seconds hand. Two consecutive examples surfaced together at auction in 2011, which is how the pairing of the 437/1 and P437/1 is known at all. III 1972 – 1991  ·  6 calibres ## The Movements That Came Back A calibre borrowed from an oval watch restarted the whole line, and its descendant still runs the smallest Reversos made today. ### Cal. 840 — “the Ovetto movement” 1972 Manual · oval The 200-piece Corvo Reverso The most consequential borrowed movement in the line’s history. When the manufacture told Giorgio Corvo it couldn’t build watches from 200 orphaned cases because there were no movements, he took the oval cal. 840 from the Ovetto, had a Milanese watchmaker build a spacer to seat it inside a Reverso case, and carried it back to Switzerland as proof. The Reverso exists today because an oval movement fitted a rectangular hole well enough to win an argument. ### Cal. 846 / 846/1 late 1980s – today Manual · 21,600 vph · 18 jewels · 93 parts · ~40 h Reverso Classique, Lady, Classic Small, Reverso One 2026 An evolution of the calibre used in the Corvo revival, and one of the great survivors: tiny, thin, beautifully made, and still running the smallest Reversos in the current catalogue nearly forty years later. ### Cal. 822 1991 – today Manual · rectangular Grande Taille, Ultra Thin Tribute to 1931, Classic Medium, Tribute Small Seconds, Hokusai enamels Built for the larger Grande Taille case in 1991 and drawn to echo the 1930s cal. 410, a modern movement wearing a period face. It is now the workhorse behind some of the most beautiful watches in the line, including the enamel Tributes, where a thin, reliable, well-proportioned movement matters more than a complication. ### Cal. 657 — the quartz years 1980s–2010s Quartz Reverso Classique, Reverso One (early), Reverso II Easy to skip past, but part of the story: the Reverso came back from the dead in 1982 as a mostly quartz watch, and quartz kept it in the catalogue while the mechanical revival was rebuilt around it. The 657 ran the smaller Classique and the earliest Reverso One references before hand-wound movements displaced it. ### Cal. 101 — the smallest of all 1929 – today Manual · 98 parts · c.0.2 g · 21,600 vph Reverso Joaillerie (c.1990); Grande Reverso 101 (2004) Not designed for the Reverso, and older than it, but no list of its movements is complete without the 101. Introduced in 1929 and still made today, it remains the smallest mechanical movement ever put into series production: 98 components weighing about a fifth of a gram. In the jewellery Reversos the winding crown moves to the back of the case, because there is no room for it anywhere else. ### Cal. 960, 970 and 977 — the automatics 1998 – 2012 Automatic Gran’Sport; Grande Automatique; Squadra Hometime The Reverso is overwhelmingly a hand-wound watch, for the obvious reason that a rotor adds height to a case that has to slide and turn. The exceptions came with the sportier families: the Gran’Sport of 1998 brought the first automatics to the line, and the Squadra and Grande Automatique carried them into the 2000s. IV 1994 – today  ·  5 calibres ## One Movement, Two Faces The engineering problem that defines the modern Reverso: driving a dial on each side of a case that turns over. ### Cal. 854 (854/1, 854A/2, 854C/2) 1994 – today Manual · two dials · ~42 h Duoface, Tribute Duoface, Classic Duoface, Fagliano The defining modern Reverso movement. One gear train, two dials on opposite sides of a case that pivots: local time on the front, a second time zone on the back, no second movement, no compromise in thickness. Thirty years on it is still being reinterpreted rather than replaced. ### Cal. 844 / 864 / 842 / 968 1994 – today Manual · dual dial, women’s sizes Duetto, One Duetto, Classic Duetto, Squadra Lady Duetto The Duoface idea shrunk. The engineering challenge is the same but the tolerances are meaner: two dials driven by one movement inside a case narrow enough for a 2:1 rectangle. The 842 adds a moon phase; the 864A powers the Ultra Thin Duetto Duo. ### Cal. 865 and 864 1997 – 2000s Manual · dual dial, women’s Reverso Duetto (1997); Ultra Thin Duetto Duo (864A) The movements that made the Duetto work: the Duoface principle in a case narrow enough for a woman’s wrist, with a discreet dial for daytime and a decorative one for evening running off a single train. ### Cal. 853 and 976 2016 – today Manual · time only Reverso Tribute Small Seconds; Grande Reverso 976 The plain hand-wound movements behind the simplest modern Tributes: no complication, nothing to display on the back, which is exactly the point when the case-back is meant to be left blank for the owner. ### Cal. 965, 966, 968 and 969 2009 – today Automatic and manual · women’s and mid-size Squadra Lady Duetto; Reverso Classic Medium and Large The workaday movements of the modern collection, the ones in most Reversos actually being sold, rather than the ones that get written about. The 968A drove the Squadra Lady Duetto; the 965 and 969 run Classic Medium and Large references today. V 1991 – 2011  ·  12 calibres ## The Complication Calibres A rectangle is the wrong shape for almost every complication in watchmaking. That turned out to be the point. ### Cal. 824 1991 Manual · power reserve · date Reverso 60ème The first complicated Reverso movement, and the first one JLC ever intended you to look at, the 60ème gave the watch a sapphire display back after sixty years of blank steel. ### Cal. 828 1993 Manual · tourbillon · power reserve Reverso Tourbillon JLC’s first modern tourbillon, and it went straight into the hardest available case. A tourbillon wants a round plate; fitting the cage, the bridges and the going train into a rectangle without thickening the watch is most of the work. ### Cal. 943 / 944 1994 / 2011 Manual · minute repeater Répétition Minutes; Répétition Minutes à Rideau The world’s first rectangular minute-repeater movement. Gongs are wound circles by nature; making them fit, and sing, in a rectangle is why almost nobody else tried. The 944 returned in 2011 with trebuchet hammers striking gongs fixed to the crystal itself. ### Cal. 829 1996 Manual · retrograde chronograph · 36 jewels Chronographe Rétrograde; Gran’Sport Chronograph (859) A chronograph organised across two faces, using a retrograde hand that flies back to zero rather than sweeping a full circle, the rational answer to a rectangular dial. Its logic reappears in the 2023 cal. 860. ### Cal. 879 / 873 / 874 / 875 2000–2003 Manual · double barrel · 8-day reserve · 28,800 vph Septantième, Grande 8 Days, Sun Moon, Grande Date Eight days of power from two barrels, married to a high-frequency balance, unusually long running time for a hand-wound watch this flat. The 879’s large-date architecture set up the entire Grande Reverso family, and its descendant cal. 834 powers the 2025 Tribute Geographic. ### Cal. 855 2000 Manual · perpetual calendar Reverso Quantième Calendrier Perpétuel Leap-year indication on the front, month, day, date and moon on the back, a perpetual calendar split across a case that turns over, closing the six-watch anniversary series. ### Cal. 823 and 823A 1999 – 2004 Manual · power reserve · moon phase · day/night Grande Taille Sun Moon; Power Reserve (823A) Three indications on one dial without crowding it: power reserve, moon phase, and a night-and-day display. The platinum Sun Moon it powered was capped at 125 pieces, the pink and white gold versions were standard production. ### Cal. 858 1998 Manual · dual time · city selector · day/night both faces Reverso Géographique (ref. 270.2.58) The Reverso’s first true travel movement: a second time zone with a city-name selector on the reverse and day/night indication on both faces. World time then left the collection for twenty-seven years, until the calibre 834 brought it back in 2025. ### Cal. 873, 874 and 875 2000 – 2003 Manual · 8-day double barrel · large date Grande 8 Days, Grande Date, Sun Moon variants The family that grew out of the Septantième’s 879: eight days of running from twin barrels, and the patented large-date display that gave the whole Grande Reverso line its identity. ### Cal. 849 — the ultra-thin 1990s – today Manual · 1.85 mm high · free-sprung balance Reverso à Éclipses; Ultra Thin SQ skeleton One of the flattest hand-wound movements in series production anywhere, and the reason certain Reversos can carry a shutter mechanism or a skeletonised dial without becoming thick. Where there is almost no room left, this is the movement that goes in. ### Cal. 944 2011 · revised 2021 Manual · minute repeater · trebuchet hammers · crystal gongs Répétition Minutes à Rideau; Tribute Minute Repeater (2021) The 943’s successor, and the movement behind two of the most theatrical Reversos ever made. Its trebuchet hammers strike gongs fixed directly to the sapphire crystal rather than the case, which is what gives it its carrying voice. Revised again in 2021 with a silent regulator and a new generation of gongs. ### Cal. 986 2009 Manual · dual dial · date · day/night Grande Reverso Duo Date A guilloché silver front with date at twelve and small seconds at six; a black reverse with luminous hands and a day/night indicator. Edition size is unsettled: an example at auction was numbered 286/500 against the 1,500 quoted elsewhere. VI 2006 – today  ·  8 calibres ## The Impossible Ones Three dials. Four faces. A tourbillon spinning on two axes. Movements built because nobody had built them. ### Cal. 175 2006 Manual · 3 displays · 18 functions · 6 patents Grande Complication à Triptyque The first movement ever to drive three dials: front, back, and a third set into the cradle the case pivots within. Civil time, sidereal time and perpetual calendar simultaneously, plus a tourbillon and an equation of time, from a single going train. ### Cal. 174 — Gyrotourbillon 2 2008 Manual · spherical multi-axis tourbillon · cylindrical hairspring Reverso Gyrotourbillon 2 Two carriages rotating on different axes (the inner one turning once every 18.75 seconds, the outer once a minute) inside a rectangle. It was the first wristwatch to use a cylindrical hairspring, and it won first and second place at the 2009 International Chronometry Competition. ### Cal. 179 — Tribute Gyrotourbillon 2016 Manual · bi-axial flying tourbillon · Gyrolab balance Reverso Tribute Gyrotourbillon; Hybris Artistica The Gyrotourbillon shrunk by roughly a third in width and thickness versus 2008, now flying, with nothing bridging it from above, and with a hemispherical balance spring and the deliberately non-circular Gyrolab balance wheel, shaped to cut air resistance. ### Cal. 185 — Quadriptyque 2021 Manual · 4 faces · 11 complications · 12 patents Hybris Mechanica Cal. 185 Quadriptyque The most complicated movement ever fitted to a Reverso, and the only one in history to drive four working display faces. Perpetual calendar and flying tourbillon; minute repeater with a digital jumping hour; and three lunar cycles (synodic, draconic and anomalistic) displayed in the cradle. ### Cal. 826 2021 Manual · digital jumping hour · moon phase · day/night Reverso Tribute Nonantième Built new for the 90th anniversary to do something the case-back had never done: a semi-jumping digital hour beside a rotating minute disc and a day/night indicator, a second complication on the reverse rather than a repeat of the front. ### Cal. 953 2025 Manual · integrated minute repeater · 7 patents Reverso Tribute Minute Repeater A wholly new integrated repeater movement, open-worked so the striking train is the view, with seven new patents. Thirty-one years after the world’s first rectangular repeater, the problem is evidently still interesting. ### Cal. 860 2023 Manual · chronograph · 300+ parts · double-sided Reverso Tribute Chronograph Takes its cue from the 1996 cal. 829 and integrates a chronograph with a double-sided time display, over 300 components in a case under 12 mm thick. ### Cal. 834 2025 Manual · world time · Grande Date (patented) Reverso Tribute Geographic A descendant of the 8-day 879, re-engineered to put world time into a rectangle for the first time since 1998, with a patented large-date display that had defeated earlier attempts at this size. Still Being Written ## Two new calibres in the last two years. Cal. 953 in 2025 earned seven patents; cal. 834 finally put world time in a rectangle. The hardest problems in this collection are evidently still open. [See the Models](https://myreversostory.com/models)