# MB&F Horological Machine No. 9 “Flow” – A Kinetic Sculpture for the Wrist The HM9 Flow arrives as a bold statement from MB&F, the Swiss atelier that treats each watch as a kinetic sculpture rather than a mere time‑telling instrument. Limited to 33 pieces per edition, the Air and Road versions sit at the intersection of avant‑garde design and high‑horology engineering. At 57 mm, the case commands attention, while the vertical time display turns the dial into a moving tableau of mid‑century automotive and aviation lines. Priced at US $182,000, the HM9 is as much a collector’s art object as it is a functional watch. Below we dissect its heritage, design, movement, wearability, and overall value, weighing the jaw‑dropping aesthetics against the very focused functionality that defines this piece. --- ## Heritage — the model's place in the brand's line and its launch context When MB&F unveiled the Horological Machine No. 9 “Flow” in 2018, it was the latest evolution of a lineage that began with the HM4 Thunderbolt and continued through the HM6 Space Pirate. Each of those predecessors pushed the envelope of mechanical architecture, and the HM9 consolidates that daring spirit into a single, streamlined package. The watch was the product of three years of development, culminating in an entirely in‑house movement that builds on the brand’s 13 years of watchmaking experience as of 2018. MB&F’s “13 years” reference reflects a period of rapid experimentation, during which the company produced fourteen distinct movements before the HM9. The Flow’s launch coincided with a broader resurgence of interest in retro‑futuristic design, drawing visual cues from 1940s‑1950s streamlined automobiles and aircraft. Only 33 copies of each of the two editions—Air (silver‑toned titanium) and Road (gold‑accented titanium)—were produced, reinforcing the piece’s status as a limited‑edition art watch. The limited run, combined with the brand’s reputation for sculptural timepieces, positioned the HM9 as a collector’s centerpiece rather than a mass‑market offering. --- ## Design & Case — case dimensions, materials, dial At first glance the HM9 is unmistakable. Its 57 mm case is described as a “triple teardrop” construction, an aerodynamic silhouette that recalls the swooping fenders of classic cars and the sleek noses of vintage aircraft. The case is forged from grade 5 titanium, a material prized for its high strength‑to‑weight ratio. MB&F employs both brushed and polished finishes on the titanium, creating a subtle contrast that accentuates the watch’s sculptural geometry. Sapphire crystal is incorporated into the case architecture, covering the vertical time display and protecting the inner pods. While the crystal is not monolithic and does not wrap fully around the pods, its presence adds a modern, high‑tech sheen and reinforces the watch’s futuristic aesthetic. The vertical time display itself is a departure from conventional analog layouts. Rather than rotating discs or traditional hands, the display presents hours, minutes and seconds in a stacked, upright arrangement. This approach transforms the dial into a kinetic tableau: as the watch runs, the numerals glide vertically, echoing the motion of a speedometer needle or an aircraft altimeter. The result is a visual experience that is simultaneously retro‑inspired and unmistakably contemporary. Two distinct editions differentiate themselves through subtle color cues. The Air edition leans toward a cooler palette, emphasizing the silvery sheen of titanium, while the Road edition introduces gold accents that catch the light with a warm glow. Both editions retain the same case architecture, ensuring that the design language remains consistent across the limited run. The watch offers a water resistance of 30 meters (≈ 3 atm), sufficient for occasional splashes but not intended for swimming or diving. No specific lug‑to‑lug measurement is disclosed, and the strap mechanism is not detailed in the source material, so we can only note that the watch is equipped with a strap appropriate to its size and weight. --- ## Movement & Performance — caliber, power reserve, accuracy Under the sculptural exterior lies a manual‑winding, in‑house calibre that is arguably the HM9’s engineering masterpiece. The movement features **twin independent balance wheels**, each housed in its own lateral pod. These balances are coupled by a **planetary differential** located in the central pod, a mechanism that averages the rates of the two balances to produce a single, unified output for the vertical time display. The central pod also contains the mainspring barrel, providing the energy that drives the entire system. By employing two balances, MB&F aims to improve rate stability: any deviation in one balance is mitigated by the other, a concept reminiscent of the dual‑balance designs seen in high‑precision chronometers. The movement is entirely manual‑wound, meaning the wearer must wind the crown regularly to maintain power. The exact **power reserve** is not disclosed in the available data, nor are any official **chronometer‑grade accuracy** figures provided. Consequently, prospective owners should be prepared for a watch that prioritises artistic expression and mechanical intrigue over extended autonomy or certified precision. Despite its singular focus on time‑of‑day indication, the HM9’s movement is lauded for its complexity. One reviewer called it “one of the most complex watches ever” from the brand, underscoring the engineering ambition that fuels the piece. However, the lack of additional complications—such as a date, power‑reserve indicator, or chronograph—means the HM9 offers a minimalist functional scope, a point that some enthusiasts may view as a limitation. --- ## On the Wrist — wearability, lug-to-lug, comfort notes Wearing a 57 mm, triple‑teardrop titanium sculpture is an experience that borders on theatrical. The watch’s sizable case naturally draws attention, and its weight—mitigated by the lightweight titanium—remains manageable for most wrists. Reviewers have highlighted the HM9’s surprising comfort, noting that “it is remarkably comfortable to wear” despite its bold dimensions. Because the watch’s case is composed of three distinct pods, the strap sits across a relatively flat surface, reducing the “pinching” effect that some large‑diameter watches impose on the wrist. The lack of a disclosed lug‑to‑lug measurement makes it difficult to assess exact wrist coverage, but the design’s aerodynamics suggest a balanced distribution of mass across the forearm. The 30‑meter water resistance indicates that the watch is not intended for aquatic activities; exposure to water should be limited to light rain or brief immersion. As a manual‑wound piece, the HM9 requires regular winding, which can be a pleasant ritual for aficionados but may be a drawback for those seeking a set‑and‑forget experience. Overall, the HM9 feels like a wearable piece of kinetic art. Its comfort level, combined with the visual intrigue of the vertical display, makes it a conversation starter in any setting where the wearer wishes to showcase a bold horological statement. --- ## When to Wear — occasion, setting and dress‑code fit Given its price point, limited‑edition status, and avant‑garde aesthetics, the HM9 is best suited for **special occasions** where a watch can serve as a centerpiece of personal expression. Think high‑profile gallery openings, avant‑garde fashion events, or exclusive private gatherings where guests appreciate design as much as function. The watch’s retro‑futuristic styling aligns well with **creative‑industry dress codes**—think tailored suits with a modern twist, or smart‑casual ensembles that incorporate metallic accents. Its titanium case and sapphire crystal give it a sleek, almost aerospace‑like vibe that pairs nicely with minimalist or architecturally inspired attire. For more formal occasions—black‑tie events, classic boardroom meetings, or traditional weddings—the HM9 may appear out of place. Its sculptural case and vertical display are far removed from the understated elegance expected in those environments. Conversely, in a casual setting, the watch can feel overly formal; its price and rarity demand a degree of reverence that may be lost in a relaxed backyard barbecue. In short, the HM9 shines when the wearer wants to **make a statement** and is surrounded by an audience that values artistic innovation. It is less appropriate for everyday wear or for settings that call for discreet timekeeping. --- ## Value & Verdict — price‑positioning + final take At **US $182,000**, the HM9 sits firmly in the upper echelon of haute horlogerie. Its value proposition rests on three pillars: 1. **Exclusivity** – Only 33 pieces per edition, each individually numbered, guarantee scarcity. 2. **Artistic Design** – The triple‑teardrop titanium case and vertical time display constitute a unique visual language rarely seen in conventional watches. 3. **Mechanical Innovation** – The twin‑balance, planetary‑differential movement showcases a daring approach to rate stability and kinetic expression. These strengths are balanced by notable **limitations**: * **Functionality** – The watch tells only the time of day; there are no additional complications, a point highlighted by critics who note the “lack of functionality.” * **Power Reserve & Accuracy** – With no disclosed reserve or chronometer certification, the HM9 cannot be judged on the same performance metrics as traditional high‑complication pieces. * **Practicality** – A 30‑meter water resistance and manual winding requirement limit everyday convenience. From an investment perspective, the limited run and the brand’s reputation for collectible art watches suggest that the HM9 could retain, or even appreciate, its value over time—provided the market for avant‑garde horology remains robust. **Verdict:** The MB&F Horological Machine No. 9 “Flow” is a masterclass in sculptural watchmaking. It delivers an unforgettable visual experience and a mechanically intriguing movement that push the boundaries of what a wristwatch can be. For collectors who prize artistic daring over functional breadth, and who are comfortable allocating a six‑figure sum to a limited‑edition piece, the HM9 is a compelling acquisition. For those who prioritize complications, long power reserves, or conventional elegance, the HM9 may feel more like a museum exhibit than a daily companion. In the end, the HM9 is less a tool for measuring minutes and more a kinetic sculpture that **flows** across the wrist—exactly as its name promises. If you are ready to wear a piece of horological art that sparks conversation and challenges norms, the HM9 deserves a place on your shelf—and, on the right occasion, on your wrist.