The MB&F LM Sequential Upgraded with a Flyback

The supercharged chronograph, now with a flyback.

In 2022 MB&F launched its first ever chronograph, the LM Sequential EVO. A twin-chronograph constructed by Stephen McDonnell, it was a clever reinterpretation of the split-seconds function. Today MB&F upgrades the concept with the LM Sequential Flyback Platinum that boasts a revised movement incorporating an additional flyback function. 

Initial thoughts

The LM Sequential Flyback is certainly polarising in terms of style and technique, like most MB&F creations. The original Sequential EVO was praised for its exceptional and creative movement construction, though the utility of the twin chronograph was debated. The LM Sequential Flyback now adds a flyback function to the package, which may seem excessive.

But that misses the point: the question of utility needn’t be answered nor asked. Such a timepiece goes far past the realm of practicality and needs to be judged simply by what it is: an incredible concept painstakingly executed.

We already explored in detail how Mr McDonnell implemented the Twinverter system of double chronographs mechanisms while making the complex movement chronometrically-potent, despite the obvious challenges. I recommend reading the original story, as it thoroughly explains the beautiful mechanical subtleties of the watch.

In the original Sequential EVO, the layered and complex construction of the movement meant the flyback function couldn’t be reliably implemented. Mr McDonnell ultimately dropped the idea and focused on perfecting the rest of the movement instead.

Two years (and surely a great deal of prototyping) later, the Irishman finally found the suitable formula, making the MB&F chronograph whole. With a case in platinum, the Sequential Flyback is undoubtedly hefty, but also mechanically dense.

Two plus one

The Flyback movement is heavily based on the original LM Sequential caliber. The McDonnell-constructed calibre basically joins two separate going and chronograph trains with one common escapement. The mirrored chronographs can work independently, just like a conventional one would, or they can be operated simultaneously. 

A clever mechanism dubbed ‘Twinverter’ makes actuating both chronographs at the same time possible. It works as a sort of binary logic gate, which depends on the chronograph trains’ state. If both chronographs are stopped or running, the Twinverter starts or respectively stopes them both. If one chronograph is running and the other is stopped, the Twinverter switches their state, stopping one and starting the other simultaneously.  

The LM Sequential Flyback adds a flyback to the many existing chronographs functions. Invented sometime in the 1930s for pilots, the flyback is an instant reset and restart function: it stops, resets and restarts the chronograph in one seamless sequence with a single press of the reset button.

In a normal chronograph, the user would have to stop, restart and then start the chronograph again by operating both pushers. With a flyback chronograph, the user only has to once press a dedicated pusher (usually the reset pusher performs double-duty as a flyback pusher as well). This allows for accurate recording of separate events in quick succession. Historically it was used for leg timing by pilots for navigation in an era before GPS.

Such a system requires some extensive tweaking of the chronograph’s operating levers and hammers, so they can accommodate the additional operation. Mr McDonnell envisioned a flyback as a part of the LM Sequential EVO from the start, and he even got to the prototyping stage, but only with a single flyback in the left-hand chronograph train. 

The LM Sequential Flyback, of course, has flyback functions on both chronograph trains.

Apart from the subtle technical addition of a flyback function, the new chronograph went through some design tweaks as well, giving it a more refined look than the original, which was substantially more sporty.

The case is platinum and measures 44 mm in diameter. Like some earlier Legacy Machine models, the case evokes vintage watches with its curved lugs bevelled along their edges. The case features five pushers, all polished, with the lower two on each side bearing “Flyback”.

The open-worked dial was similarly facelifted. The EVO featured flat black sub-dial rings clearly designed to be functional, with the chronograph works taking centre stage. Here the register scales are finished in glossy white lacquer that resembles fired enamel.

The time-telling miniature dial at six o’clock is now angled towards the user, which not only enables time reading but also visually separates the timepiece’s indications.

The domed sapphire crystal is filled up nicely by the angled sub dial and the trademark raised balance wheel. The movement beats at a leisurely paced 3Hz rate, with the big free-sprung balance featuring a pleasantly prominent Breguet overcoil.

Most of the chronograph works are laid bare and exquisitely finished, as is tradition with the Legacy Machine series. The various polished and brushed steel components contrast well with the “sky blue” base plate. According to MB&F, the colour is a nod to the history of the flyback function, since it was invented for aviation. 

On the back, the movement is slightly more orthodox than the front. A keen observer can make out the twin barrels and going trains. The two barrels run in parallel to ensure a 72 hour power reserve.

Like other Legacy Machine, the movement has several classical elements mixed into the modern construction, making for an overall traditional aesthetic. The dark grey bridges are bevelled and decorated with Geneva stripes. Many jewels sit in golden chatons. The visual highlights are two abnormally large minute counter wheels.

Key Facts and Price

MB&F Legacy Machine Sequential Flyback Platinum

Diameter: 44 mm
Height: 18.2 mm
Material: Platinum
Crystal: Sapphire
Water resistance: 30 m

Movement: Chronograph movement developed by Stephen McDonnell
Functions: Hours, minutes, power reserve indicator and twin flyback chronograph function
Winding: Hand-wound
Frequency: 21,600 beats per hour (3 Hz)
Power reserve: 72 hours

Strap: Alligator leather strap with white gold folding buckle

Limited edition: 33 pieces
 At MB&F retailers and MAD Galleries
Price: US$218,000 before taxes

For more, visit


Back to top.

You may also enjoy these.

IWC Unveils Experimental Luminous Ceramic Case

Patent-pending Ceralume in a Pilot's chronograph.

IWC just revealed an experimental Pilot’s chronograph with a luminous ceramic case – on the wrist of Formula 1 champion Lewis Hamilton at the Monaco Grand Prix. Christened Ceralume, the material was developed XPL, the watchmaker’s experimental engineering department. According to IWC, the Ceralume concept watch was glowing a bright blue for more than 24 hours in dark chamber tests (although it didn’t state how the material was “charged” prior to the test).

According to IWC, the patent-pending material is created by blending ceramic powder with Super-Luminova, the luminous material produced by RC Tritec that absorbs light energy and then emits it. Being non-radioactive, Super-Luminova is widely used to illuminate watch dials, and also suited to a case material. Though IWC has not revealed specifics about future plans for the material, it did say Ceralume will “form the foundation of future developments and releases.”

Lewis Hamilton at the 2024 Formula 1 Monaco Grand Prix

Initial thoughts

Ever since the discovery of radium in 1898, luminous materials have become commonplace in watches, primarily to aid legibility. With legibility being less crucial today, luminous paint is increasingly used for purely aesthetic purposes.

Moreover, luminous ceramic is not actually new. Tudor, for instance, used luminous ceramic hour markers in the Black Bay Pro of 2022. IWC is the first to make an entire case from the material, albeit not one that is available commercially (yet).

The luminous Pilot’s chronograph, however, is cool. In fact, the concept watch is essentially a cooler version of the Top Gun Lake Tahoe in white ceramic, one of the brand’s bestsellers. It is certainly something I look forward to seeing in regular production, although IWC’s recent watches in experimental materials have been arguably too pricey.

Glow-in-the-dark ceramic

According to IWC, the development of Ceralume took several years. One of the primary obstacles in perfecting the material was achieving a “homogeneous mix of [ceramic powder and Super-Luminova pigments] despite their different particle sizes and avoiding particle accumulations.”

The right mix was obtained by utilising a “ball milling process” to machine the raw case before it is sintered (or baked) in a specialised oven. IWC also tweaked the sintering and grinding processes to suit the material.

With the material perfected,  XPL created the luminous concept watch. Based on the Pilot’s Watch Chronograph 41, it has a Ceralume case along with a luminous dial matched with a luminous rubber strap. Both the dial and strap are manufactured in conventional manner: the brass base of the dial was coated with Super-Luminova before the markings were printed, while Super-Luminova was added to the synthetic rubber as the strap was injected moulded.


Back to top.

You may also enjoy these.

Obituary: Antoine Simonin, WOSTEP Director, Educator, and Bookseller

A personality who left a legacy.

Antoine Simonin (1938-2024), who died on May 20 at the age of 84, left his mark on generations of watchmakers and watchmaking enthusiasts. He will be best remembered as the director of WOSTEP (Watches Of Switzerland Training Educational Program) from 1976 to 2003.

Simonin was a person obsessed with the transmission of watchmaking knowledge, and sought to make WOSTEP an instrument for the international dissemination of watchmaking mastery. Founded in 1966, WOSTEP sought to train watchmakers capable of maintaining and repairing Swiss-made watches according to the standards laid out by their makers, the Swiss watch industry. Over time, its courses have been taught in English, French, German, Japanese, Swedish, and Mandarin.

“I studied at WOSTEP under Antoine Simonin in 1987 and 1991,” says Peter Speake, the watchmaker best known for founding Speake-Marin, “He was instrumental in keeping WOSTEP going during that difficult industry period, subsequently influencing the careers and friendships of many watchmakers, directly and indirectly, playing a significant role in the lives of many crossing multiple generations.”

Recounts another student, Paul Francis Madden, now himself an instructor at WOSTEP, “I was a student in 1987, back when the staff at WOSTEP was only Mr Simonin and his wife Josiane… It came to showing him my first hairspring… He slowly spun my balance wheel in his callipers, scrutinising it for what seemed like an eternity, and all without saying a single word. It was agonising!”

“He placed the callipers gently on his bench, looked me in my eye and said: ‘I hope your life will be as well-centred as this hairspring Madden. It’s perfect’. To hear those words from Mr Simonin was, and still is, one of the great moments I look back on in my watchmaking career.”

The WOSTEP 50th anniversary celebration with Antoine Simonin at bottom centre in maroon jacket. Image – WOSTEP

Keeping the watches going

WOSTEP is now an institution which welcomes numerous students each year. During his tenure, the training offered by the school grew to become a 360-degree coverage of after-sales service, to the point that today WOSTEP trains watchmakers-repairers, trainers for brands and schools, retailers, customer service employees, case polishers, and also specialists in chronograph, regulation, movement finishing, and so on.

In the 1990s, I remember raising the subject of WOSTEP’s role and usefulness. Simonin told me, “Switzerland exports its watches to five continents. We must ensure that their sustainability is guaranteed by their knowledge.”

Nothing visionary, but the point showed a keen realism: how to ensure after-sales service for a watch, especially a complicated one, on the other side of the planet? This was his mission: to disseminate watchmaking skills in the main export markets for Swiss watchmaking.

“His expertise in the field of training was internationally recognised and unparalleled,” says François Bauder, International Customer Service Director at Patek Philippe and trustee of WOSTEP, “Working with Antoine Simonin has enriched me both professionally and personally for more than twenty years. My meeting with him in 2003, as part of WOSTEP projects, marked the beginning of an invaluable learning experience.”

“He had a knack for picking the right fights and leaving aside the ones that weren’t worthwhile, often illustrating his approach with the popular saying ‘let the sheep piss’,” continues Mr Bauder, “Antoine inspired many people… I feel a deep sadness to have lost a guide, but also a great pride to have had the chance to work with him and learn from him.”

WOSTEP in Neuchatel. Image – WOSTEP

Boards and books

A watchmaker himself, Simonin was passionate about chronographs and grand complications. The extent of his knowledge and his entrepreneurial spirit earned him the prestigious Gaïa Prize in 1995. He was similarly honoured with the Special Jury Prize of the Grand Prix d’Horlogerie de Genève (GPHG) in 2020.

His expertise also gained him positions in organisations governing the destiny of Swiss watches, amongst them president of the technical commission of Qualité Fleurier, the testing and certification body, and of Chronométrophilia, an association for the history of time measurement.

He was also a member of the commission of the Musée International d’Horlogerie (MIH) of La Chaux-de-Fonds, and collaborated with the Federation of the Swiss Watch Industry (FHS) as an expert in the update of what remains the reference for any amateur or professional watchmaking, the Illustrated Professional Dictionary of Horology, more commonly known as the “Berner” after its author, G.-A. Berner.

In 1980, Simonin embarked on another route of transmitting knowledge, by opening a bookstore, Editions Simonin, offering all imaginable literature on watchmaking.

Pascal Brandt has been a freelance watch journalist for ten years. He started his career at watch magazines before joining Officine Panerai in Milan as head of communications, after which he held senior roles at Vacheron Constantin and Bulgari. He is now a consultant for public relations at Parmigiani Fleurier.

Correction May 29, 2024: The author of this article is Pascal Brandt; the story was earlier attributed to the wrong author.

Back to top.

You may also enjoy these.

Welcome to the new Watches By SJX.

Subscribe to get the latest articles and reviews delivered to your inbox.