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MB&F Horological Machine
Photo by MB&F (CC BY-SA 4.0), via Wikimedia Commons · stand-in: MB&F HM3 Frogs, same Horological Machine series as catalog ref HM9 Flow (HM9-FL-TI-MT); HM3 vs HM9 model, same signature twin-turret HM architecture.
  • MB&F Horological Machine

Horological Machine

MB&F’s sculpture-on-the-wrist line: each Horological Machine is a different three-dimensional architecture, with the case shape designed first and the movement engineered to fit. HM1 launched the brand in 2007; HM11 Architect (2023) is the current production reference, a round-bezel-with-four-rotating-arms case that doubles as a thermometer. The line is the most-distinctive contemporary watchmaking outside the round-case canon.

Year introduced: 20072 references

References in this family

Which ref to buy

The Horological Machine series is MB&F's core product line: three-dimensional spacecraft-shaped cases with movements developed by independent watchmakers under Max Büsser's direction. Each numbered HM is a unique machine. HM11 Architect is the most recent; HM9 Flow is inspired by aerodynamics. No two machines in the series are alike.

  1. 1

    HM11 Architect: 3D skyscraper case architecture, co-developed with Kari Voutilainen, the most architecturally sophisticated HM.

    The case for it:
    The HM11 represents MB&F at its most ambitious: a three-dimensional case architecture with vertical time display and movement collaboration with one of watchmaking's most respected independent makers. For a collector who wants to own the most sophisticated version of the HM concept, this is the correct choice.
    Consider instead if:
    MB&F secondary market requires patience. The HM series commands strong prices but is illiquid — there are not many buyers. Urwerk and similar mechanical-art brands occupy the same buyer pool with similar liquidity characteristics.
    Open
  2. 2

    HM9 Flow: aerodynamically-inspired biomorphic case, twin turbine winding system, sapphire crystal "cockpit."

    The case for it:
    The HM9 Flow is the MB&F that reads as most organically beautiful. The aerodynamic case language and the twin-rotor winding system are visually coherent in a way that some other HMs are not.
    Consider instead if:
    HM11 is the newer and more technically ambitious machine. If you can acquire either, the HM11 is the more significant piece in the series progression.
    Open

Rankings last reviewed 2026-06-18. Editorial perspective only. Not financial advice.

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