The MB&F HM9 Flow

The MB&F HM9 Flow

With sweeping curves, bulging glass canopies and flowing contours, the latest MB&F Horological Machine is strongly reminiscent of the streamlined auto and aero designs of the hazy days of the 1950s. Introducing the HM9 Flow.

MB&F HM9 Flow

A futuristic blast from the past

Never does an MB&F wristwatch launch come along that doesn’t command watch lovers the world over to their screens, to be among the first to witness the latest chapter in the legacy of a brand who never fail to come up with the goods.

MB&F HM9 Flow

Just what is it about MB&F that has collectors, journalists and enthusiasts alike gravitating en masse, as if summoned by some form of higher power, toward their nearest screen as the reveal hour approaches, and a new watch breaks cover for the very first time? Let’s face it, if you wanted a watch that is quickly and easily referenced to tell you the precise time, well a flat round disc with a pair of hands has been servicing that role for centuries, in a fairly successful solution that has varied very little from its formative days. So when it comes to that very basic principle, being totally honest and matter of fact about it, sometimes MB&F don’t really give two hoots if you have to engage a few brain cells to figure it out.

What perhaps if you want a watch that discreetly fits in anywhere, be it in the bank manager’s office, at a wedding or maybe a funeral? Nope, not really. The bank manager will think you’re upstaging him, the bridegroom will think you have ideas on his new wife, and at the funeral all of the talk will be about your MB&F rather than how decent a fellow poor Bob was. You see, an MB&F watch might be an exercise in overkill for some.

MB&F HM9 Flow

And when it comes to price, well for most mere mortals you don’t just save up your money to buy one; MB&F are pretty much the exclusive reserve of society’s better resourced individuals, and so one of the benefits of writing about watches is that sometimes I get to cosset one against my own skin for an always too brief experience.

So, on balance of all these requirements, it might seem as if an MB&F does have a number of shortcomings, or perhaps is not such a great all-rounder when it comes to just being a watch, and doing typical watch-y things for the typical watch-y customer. Well, okay.

Why then do I suspect that I might willingly bid adieu to one of my limbs if Maximillian Büsser offered me one of his watches in return? Why do all the little things that make an MB&F so impractical as a precise measurer of time matter not one iota? Why do I, like all the others feel the need to be on hand at launch time so irresistible? Why, when I look at the faces of the MB&F ‘Friends’ do I feel a little pang of envy, like the schoolboy who spends each breaktime on his own in the schoolyard, and the feeling that if your face isn’t among the coolest club in Watchville, you’re on the outside, and probably wasting your life.

Why? Well, because MB&F transcends the definition of what a watch is. In terms of a common sense timepiece it’s maybe lesser than others, but in its pure expressive language it’s much, much more than any other watch. It’s an object which stirs the emotions. An object of intrigue, of fascination and expression, and of great desire.

If there are those who might dismiss its form and functionality as frivolous (and there probably are; humanity has revealed itself to be capable of some very strange thinking), then they are missing the point entirely, and if the brand’s philosophy isn’t already obvious, then there’s a hint in the names of its creations that gives it away. These are not mere watches, these are Horological Machines, and that distinction means that when it comes to design and watchmaking innovation, there are no rules; these pieces are the product of the unrestrained imagination of the boy Büsser, inspired by the playthings and the innocent sci-fi imagery of futuristic forms of transportation which surrounded him.

MB&F HM9 Flow

Their exclusivity and form places an MB&F in the same pantheon as the green Porsche 911 Turbo, or that red Lamborghini Countach, which themselves were immortalised in poster form in adorning the bedroom walls of countless young lads; where a boy could study the minutiae, memorise the performance figures on his Top Trump cards, and dream. And that I think is why many more than will ever be a customer are compelled to tune in to witness a new creation.

It never disappoints. Evoking the post-war era of aerodynamic advancement in almost anything that moved, Horological Machine No.9 ‘Flow’ is a spectacular curvilinear trigonal construction, with a central cylinder fronted by a dashboard like dial, and flanked by a pair of streamlined capsules, like twin vintage motorcycle sidecars with domed sapphire canopies, and which taper forward to a gleaming rounded leading point. Part aircraft, part automobile, HM9 is metal and glass sculpture, which celebrates the airflow conscious designs of the 1950s and ‘60s, which often had no basis in science but which looked fabulous.

So overt are these influences that the word ‘fuselage’ seems more fitting for its smoothly contouring titanium case, and as its beautifully formed profile tapers front to rear, with the dial housing like a jet engine intake, from almost any angle it effuses the sensation of speed, and head on HM9 Flow looks like it’s coming your way in a hurry. Or is it going away? Maybe. Apply your own imagination.

MB&F HM9 Flow

The time is displayed vertically, on a choice of two dial options, for there are two limited edition models of 33 pieces each; the Flow Air, with aviator style dial markings, and the Flow Road whose inspiration is the speedometer of a classic Mercedes. Both are clear and easy to read, and there’s no great effort required to tilt the display to check in on the time, as you will. Often. Apart from the colouration of the movement, because in the Flow Road it is plated with rose gold, while Flow Air features a dark NAC coating, both editions are otherwise identical in every respect.

MB&F HM9 Flow

Comprising forty three parts, the case is so complex that MB&F struggled to convince its case manufacturing partners that it could be done at all, but persistence, and a soupçon of Maximillian Büsser’s magical touch, where impossible things just seem to materialise, has certainly paid off. I’ve a distinct feeling that he would be a hard man to say ‘no’ to.

The central element is a tapering cylinder, reminiscent of an old jet engine, whose rake narrows down its length until culminating at the grooved, semi-conical crown, which is at the opposite end to the dial binnacle that’s bolted onto the case body.

The surfaces of HM9 Flow are mainly finished with a brushed grain, although the detailing, such as the seam lines which define the join between the side pods and fuselage, and where the two halves of the case meet, are polished, as is the underside. Behind the dial binnacle and along these seams, a challenge was to create a gasket which could ensure a degree of water resistance, and to get an idea of how tricky that was, imagine that it required new patents to achieve an effective three dimensional solution.

MB&F HM9 Flow

Beneath a domed panel of sapphire crystal, which effectively resembles a cockpit canopy, the ‘engine’ at the heart of the HM9 is revealed, and on either side it is flanked by a pair of bulbous pods which sprout outwards with the fluidic lines of a water droplet, each of them covered with a sapphire glass, and beneath which twin balance and escapements, suspended from an arcing polished wishbone, provide the animation, and whose energy release is equalised and governed amidship by a differential which then ensures a constant delivery to power the mechanism.

To achieve what MB&F needed there was no precedent, although aspects of HM9 have been seen before in earlier models, and so the movement had to be designed and developed entirely from scratch. Unsurprisingly there are no off the shelf alternatives and almost every component is bespoke to this piece and this piece only, which is technically demanding, but in reality, it has to be made to measure when a Horological Machine needs a heartbeat.

MB&F HM9 Flow

The result would hold up as a work of art in its own right, and the architecture of the manual winding calibre really is a triumph of horologic ingenuity and problem solving; matters which are nothing new to MB&F in getting a new concept across the finishing line. Fully wound it is good for some forty five hours of autonomy, and it operates at 18’000 vph.

The attachment points for the strap are on the underside of the case, and as the strap is cut out around the protruding dial at one end, and the crown at the other, the piece is allowed to articulate to ensure a comfortable fit on almost any wrist size, despite measuring 57mm in length and 47mm across.

Did I mention that it’s extraordinary? Did I say that it’s exquisite? Did I remember to say that in each and every detail it is immaculately executed, or how perfectly put together it is? Maybe how utterly irresistible to the eye it is? I might have forgotten to, but it’s all of those things. After all, when has an MB&F not been?

So there we have it I guess. A new MB&F which like all of its predecessors blurs the line between the wristwatch and an objet d’art, HM9 Flow is an incremental evolution of technical and manufacturing prowess, and throughout there are myriad little details which will absorb most who will get to see it. But even if you’re one of those who will not, surely there’s a space for it on that bedroom wall, between the Porsche and the Lambo.

Horological Machine No. 9 ‘Flow’ Fact file:



  • CASE SIZE: 57mm (l) x 47mm (w) x 23mm (h)

  • CASE MATERIAL: Grade 5 titanium and sapphire glass

  • DIAL: Vertical

  • MOVEMENT: Proprietary manual winding calibre, 18'000 vph

  • POWER RESERVE: 45 hours

  • FUNCTIONS: Hours, minutes

  • BRACELET/STRAP: Alligator

  • BUCKLE: Pin buckle


  • PRICE: CHF 168’000