Manufacturer | MB&F |
Caliber Number | HM8 Mark 2 |
In-House? | Yes and No (see below) |
Base Caliber | Girard-Perregaux (caliber number unconfirmed) |
Type | Automatic, self-winding mechanical |
Jewels | 30 |
Number of Parts | 247 |
Power Reserve | 42 hours |
Beat Rate | 28,800 bph (4Hz) |
Lift Angle | Unconfirmed |
Regulator | Triovis style |
Anti-Shock Device | Kif |
Functions | Optical vertical display of hours (left) and minutes (right) |
Features | 22K gold automatic winding rotor |
Country of Manufacture | Switzerland, Swiss made |
Known Models | MB&F HM8 Mark 2 |
The MB&F HM8 Mark 2 is a Swiss made inverted automatic movement based on a Girard-Perregaux digital jump hour caliber with an in-house module. This caliber was announced on June 13, 2023 in the HM8 Mark 2 “driver’s” watch.
Some of the topics covered in this caliber listing:
What is an “inverted” automatic movement?
At a first glance from the back of the watch, you might think the HM8 Mark 2 is a manual-wind movement. Flip the watch over and you quickly realize that is not the case.
Traditionally, an automatic watch movement will have an automatic winding unit with a spinning rotor or oscillating weight on the bottom. An inverted automatic movement is a watch movement that has the rotor on the dial side or top of the watch, usually for visual effect.
About the Time Display:
The HM8 Mark 2 features digital style jumping hours and minutes displayed on the front side of the watch. This design was inspired by vintage Amida Digitrend drivers watches (introduced in 1976). The idea with this type of display is so that you can easily see the time with your hand on the steering wheel of an automobile.
To achieve this display, MB&F did not simply redesign the wheel. Unlike the Digitrend and similar watches of yesterday which have small vertically-situated dial discs (one for hours and another with minutes), the discs on the HM8 Mark 2 are positioned in the traditional horizontal – or on top of the movement – flat position. And this is where MB&F, a brand that prides itself in exploring childlike imagination, makes magic.
The flat-laying dials are beamed to the side of the watch via high-precision sapphire prisms. The front-facing vertical viewports are 90 degree projections of the discs that otherwise would be out of frame when you’re gripping the wheel of your roadster. The brand calls it optical engineering.
To add to the cool factor here, the prism appears to relay the image with subtle distortions or a fisheye effect, which mirror the overall aesthetic of the watch. This, of course, has not been confirmed in real-life since the piece has only been presented to CC via stock photos, but it does appear to be the case.
Modularly In-House:
The MBF HM8 Mark 2 is not considered to be a fully in-house caliber because it is based on a Girard-Perregaux movement. Caliber Corner has reached out to MB&F for further clarification as to the base caliber used, and this post will be updated accordingly.
While the base movement is a GP, MB&F makes it clear that module for the jumping hour and trailing minutes was developed in-house. And, let’s face it, what would this piece be without that inventive addition.
It’s interesting to note that with the extensive reworking of the mechanism to achieve the HM8 Mark 2’s unique functionality, MB&F surely could have gotten away with labeling this movement as “in-house” in their press materials. Instead, they chose to be transparent (at least about the base caliber origin, not the caliber designation), and shared in the press-release that the base was GP with an in-house module. Many enthusiasts would just take it for granted that a haute brand like MB&F is 100% in-house. At the end of the day, the HM8 Mark 2 is clearly no longer a GP, but the connection and history are important.
Caliber Number:
As seen with the innovative designs in their timepieces, it’s clear that MB&F doesn’t color within the lines, they are independent in every sense of the word. This even carries over into the way they designate their calibers. Unlike most brands that use a numbering system, MB&F calls this caliber by the same name of the watch itself.
This movement is in the HM8 Mark 2 line of watches, therefore, the movement is considered to be MB&F caliber HM8 Mark 2.
Macro Gallery:
Video:
Watches with this movement:
At the time of initial launch (and at the time of this post), the @mbandf caliber HM8 Mark 2 is available in one model with two color variations:
- HM8 Mark 2 – White CarbonMacrolon body panel
- HM8 Mark 2 – Green CarbonMacrolon body panel (limited edition with only 33 available)
The retail price is the same for either color: 68’000 CHF or 73’000 CHF with VAT (About $78,000 USD).
Additional Resources:
- MB&F HM8 Mark 2 official page
- HM8 Mark 2 press-release (pdf)
- Shop HM8 Mark 2 at M.A.D.Gallery
- User manual for the HM8 Mark 2 (pdf)
Creative Credits:
- Images source: MB&F
- Movement photographers: @laurent_xavier_moulin and @gustavokuri
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