When MB&F first revealed the Legacy Machine Sequential Evo in 2022, the brand’s third major collaboration with Belfast-based watch designer Stephen McDonnell, it won the overall top prize, the Aiguille d’Or, at the year's Grand Prix d’Horlogerie de Genève (GPHG). While their first collaboration, the Legacy Machine Perpetual, presented McDonnell’s fresh take on the perpetual calendar, the Legacy Machine Sequential Evo rethinks the chronograph as we know it.

The 44mm case is crafted from zirconium, a metal known for its twin properties of hardness and lightness compared to the more conventional choices such as stainless steel and titanium. The case features a polished bezel, satinated midcase and a polished display caseback secured by eight screws. In the midcase are the five polished square pushers as well as the crown. The short lugs, high-polished on the top, have brushed facets and profiles. They curve down dramatically and on them is a white rubber strap, each secured by three screws visible on the movement side of the case. They come together with a double-fold, spring-loaded clasp, signed with the brand mark.    

The minimal bezel affords more real estate to the dial-free aesthetic under the domed crystal. The four-armed balance wheel is secured by the familiar twin-arm bridge that towers over the rest of the dial. North of it are the twin 30-minute counters, while to the south of the balance lie the two large chronograph seconds registers. These wear a similar layout – a chapter ring with white printed numerals and baton markers, while the centres show off the thoughtfully crafted mechanics underneath, with bridges and components mirroring each other's form. The chronograph minutes are tracked by white hands with arrow pointers, while the chronograph seconds hands are simple, slim batons.

McDonnell’s innovation involves two independent vertical clutch chronographs linked by a Twinverter mechanism. While the chronographs can individually be engaged by their respective pushers, the fifth pusher at 9 o’clock governs the functioning of the chronographs when they need to be run in parallel to time to simultaneous events, or in sequence to time successive laps. The elegant solution affords a level of functionality that is absent even in most rattrapante chronographs.

Flanked by the two chronograph seconds registers, at 6 o’clock, is the time-telling display. The register is the only solid one, aiding time-reading ease. Set against a rich black, the printed white baton hour markers offer visual contrast, as do the white, arrow-tipped hours and minutes hands. This register, that also wears the brand mark printed in white, is set against the grey, radial sunburst base that frames the dial side.  

The theme of symmetry, peaking from under the registers on the dial side, continues onto the movement side as well. The two large, thin-rimmed intermediate wheels of the chronograph sit atop the gold minute counter wheels as well as those of the twin going trains. Further down, secured by a single, irregularly shaped bridge, are the twin mainspring barrels, arranged vertically. They are slightly different in size, but this arrangement is crucial not just to providing the manual wind calibre with 72 hours of autonomy but also for accurate timekeeping even with both chronographs engaged. Another bridge at 7 o’clock features an up-down-style power reserve indicator.

The larger bridges wear rhodium plating, giving them a darker appearance. They wear Côtes de Genève while the smaller, triangular bridges are mirror polished. All bridges bear sharp anglage and many of the visible jewels, such as the ones anchoring the mainspring barrels, are ensconced in gold chatons. The watch designer’s name is etched in an elegant calligraphic font, as is the jewel count and the country of origin.

The Legacy Machine Sequential Evo, that comes with its display box as well as its warranty paperwork, features not just a landmark movement by one of Britain’s finest watch designers, but also one of the rare instances of true mechanical innovation in modern watchmaking.

Closer look

Condition

This MB&F Sequential Evo is in excellent overall condition and is practically unworn. It comes with the original boxes and paperwork from MB&F, signed by the authorised retailer, along with a selection of black, white and yellow rubber straps.

Warranty

The watch comes with a lifetime guarantee of authenticity from A Collected Man as well as the remaining duration of the manufacturer warranty from MB&F.

MB&F have additionally offered a complimentary service to the future owner which can be exercised within the first 6 months of purchase, extending the warranty by a further two years from the date of completion.