It is very rare for a watch to reimagine a function or a complication, but that is what the H. Moser & Cie Streamliner Perpetual Calendar does. If you already know what a perpetual calendar is, but are unaware of H. Moser & Cie’s particular take on it, you will have a hard time even understanding the Streamliner Perpetual Calendar. To begin with, the H. Moser & Cie Streamliner Perpetual Calendar will allow you to keep track of the date, month and leap year effortlessly. All the information is displayed precisely and discretely — there are no confusing subdials here with overlapping information. The all-new calibre HMC 812 does the heavy lifting, and we will come back to it. What is important to understand here, in advance of getting into the mechanical details, is how the watch provides its information. 

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It looks like the H. Moser & Cie Streamliner Perpetual Calendar simply indicates the date, via an impressively proportioned double-disc date window at 4 o’clock. This display is not the typical one disc for units, and one disc for 10s. Instead, they are superimposed, operating one after the other; one disc runs from 1 to 15, with the second disc taking over from 16 to 31. This clever solution means that instead of the date being forced to move from 30 to 1, for example, the active discs simply switch places. Unfortunately though, the precise alignment of the discs means the three-dimensional Globolight inserts used to give the hour and minute hands their luminescent properties cannot be used here, according to H. Moser & Cie CEO Edouard Meylan. Instead, both date discs use Superluminova. Still, this is a rare perpetual calendar that makes its date mechanism glow in the dark. 

Take a moment to study the dial; can you tell how the Streamliner Perpetual Calendar shows the months? Here’s a hint — take a look at that short central hand with the white decal and red highlight. So this watch below is showing December 12 on its fumé dial, a H. Moser & Cie signature. The logo in transparent lacquer is yet another brand signature, making the watch less like a brand statement and more like a beautiful timekeeper. That is exactly as H. Moser & Cie likes it, although it might be a little confusing for the uninitiated. If you are at all flummoxed, we suggest you check out our previous stories on H. Moser & Cie, as well as the other Streamliner models. 

Back to the perpetual calendar indication, this will certainly not be to everyone’s taste. That is fine because H. Moser & Cie watches are not for everyone, and do not try to be. What is important to note though is if you prefer instantaneous date changes, you will get it here. The watch can also be set without worry, forwards and backwards, at any time. You will not have strange rules to remember and follow, lest you break the watch. 

It is a pretty tough ticker overall, in fact, so you can actually take it running, or swimming even. It is water-resistant to 120 meters, and a full wind lasts seven days, minimum. This level of toughness is truly very rare for a perpetual calendar. This makes the experience of wearing the H. Moser & Cie Streamliner Perpetual Calendar quite different to most other sorts of perpetual calendars. Happily, the watch presents as its name suggests — streamlined. At 42.3mm wide and 11mm thick, it wears well even on smaller wrists; we shot a video to prove this and you will be able to watch it soon. The integrated bracelet design, with its fluid lines and articulated links makes for a great wearing experience. If you have tried any of the Streamliner watches, that will give you a good gauge.

About the manual winding calibre HMC 812, it is fully developed and realised by H. Moser & Cie, right down to the Straumann balance spring, the gold escape wheel and pallet fork and the distinct modular escapement architecture. This particular movement also comes with direct central seconds, rather than the subdial used in the Endeavour Perpetual Calendar. The combination of microblasted laser finishing and anthracite rhodium plating lend the movement a contemporary finish. 

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As a bit of a cautionary note, fans of perpetual calendars should take note of all the particularities, just as traditional finishing proponents need to know where to examine calibre HMC 812. If you like the elaborate Jura and Geneva style movement finishing and date indicators, this one might leave you thinking the watch is too cool for school. If you like a day-of-the-week indication, you are out of luck here. The leap year indication is executed on the movement-side, visible via the exhibition caseback. Finally, if you like the once-in-four-years experience of seeing all indications change at the stroke of midnight, you will not quite get that feeling.

For more information about the H. Moser & Cie Streamliner Perpetual Calendar, click here.