Independent Watchmaking - May 20, 2020


The relationship between man and watch is as nuanced as the one between man and dog. The best examples of such connections last for years, even decades, shaping lives and stories. In some cases, the watch chooses its owner as much as the other way around. After all, whether it’s your first or hundredth time, there’s something special about the moment you set eyes on The One. So it is, as they say, with Man’s Best Friend. Presenting Horological Machine N°10 ‘Bulldog’.

A rounded, compact body of titanium or red gold, coupled with a generous ration of sapphire crystal. Two prominent aluminum time-display “eyes”, rolling at anyone who dares look its way. A collar studded with projections that allow you to wind the mainspring or set the time. Stout but flexible “legs” that wrap firmly around your wrist. A massive jaw. And above all, a big heart beating steadily at 2.5Hz (18,000vph).

Just like the creature for which it is named, there’s more to HM10 Bulldog than meets the eye. Its hinged jaws open and shut according to the amount of wind left in its mainspring — a fully closed mouth tells you that “Bulldog” is wound down and ready for a nap. If you can clearly see the rows of shining teeth lining the jaws, get ready, because that means “Bulldog” is full of fight, charged up with 45 hours of mainspring energy. This massive power-reserve indication has been carefully designed and calibrated to consume the least energy possible, allowing HM10 Bulldog to direct its considerable mainspring torque solely towards its suspended balance and its revolving hour and minute domes.

The manual-winding engine of HM10 Bulldog was designed and developed in-house, leveraging the best of MB&F’s technical expertise built up over the years; longtime members of the MB&F Tribe will recognize elements that hew closely to the horological lab’s best-loved creations. The large suspended balance that hovers just beneath the central dome of sapphire crystal was made possible by the various iterations of this mechanism in the Legacy Machine collection. The massive jaws that indicate the level of mainspring wind are a much-expanded demonstration of the power-reserve management that was first deployed in the 2014 LM 1 Xia Hang. The paper-thin aluminum domes have their roots in the HM 3 Frog and were refined in 2014’s HM 6. Even the grillework design motif in the “ribs” set beneath the balance and in the tail-end of the body echoes the automotive-inspired HM 8, HMX, and HM 5. Taken altogether, the message is clear: HM10 Bulldog is a highly bred machine.


The mechanics driving Horological Machine N°10 ‘Bulldog’ are entirely new but deeply familiar. Completely designed and developed in-house, the HM10 engine is the technical confluence of the various areas of movement expertise at MB&F, honed over years of experience.

The eye-catching balance, suspended beneath the central sapphire crystal dome and beating at the traditional cadence of 2.5Hz (18,000vph), first appeared in an MB&F creation in 2011, with the debut of Legacy Machine N° 1. Since then, this technically challenging mechanism has become a unique icon of MB&F, appearing in the majority of Legacy Machines, Horological Machine N° 9, and now HM10 Bulldog.

The most powerful and startling, the revolving time-telling domes of HM10 Bulldog originated in the conical hour and minute-mod-rules of the first Horological Machine N° 3, the creation that cemented MB&F’s reputation as a disruptive horological force. Subsequently, the cones took on rounded forms in HM 3 ‘Frog’, but the one factor that remained constant was the urgent need to make them as light as possible so that they placed minimal stress on the rest of the engine. Conventional milling processes were reworked and tolerances were sliced micro-fine in order to produce paper-thin aluminum components in three dimensions. These components later appeared again in Horological Machine N° 6, this time paired with conical gearing to enable the highly precise display of time.



Horological Machine N°10 ‘Bulldog’ is available in two versions: – Ti version: grade 5 titanium case with a blue hour and minute domes; – RT version: 18k red gold and titanium case with black hour and minute domes.


Manual-winding in-house movement Frequency : 2.5Hz (18,000bph)

Bespoke flying 14mm balance wheel with four traditional regulating screws floating above the domed dials

Super-LumiNova on the hour and minute domes and markers

Single barrel with 45 hours of power reserve 301 components, 34 jewels

Left crown at 11 o’clock for winding; right crown at 1 o’clock for setting the time


Hours on the left dome (aluminum dome rotating in 12 hours)

Minutes on the right dome (aluminum dome rotating in 60 minutes)

Power reserve indicated in 3D by the opening and closing of the jaws (end of power reserve = closed jaws).

CASE Version

Ti: grade 5 titanium Version RT: 18k 5N+ red gold and grade 5 titanium

Dimensions : 54mm × 45mm × 24mm Water resistant to 5ATM / 50m / 160ft


2 sapphire crystals treated with anti-reflective coating on both sides


RT version: hand-stitched brown calf-leather strap with custom-designed red gold folding buckle. Ti version: hand-stitched blue calf-leather strap with Velcro system and a titanium buckle.