On the surface, the Streamliner Perpetual Calendar by H. Moser & Cie seems to sport a smooth yet unassuming design but upon closer inspection, it becomes apparent that its minimalist appearance belies its true complicated nucleus.

Flipping the watch would instantly prove this conjecture, its see-through back revealing the heart that powers it: the all-new HMC 812 calibre, a uniquely simple hand-wound Perpetual Calendar movement. 

After marking its return to Haute Horlogerie with the introduction of the Perpetual 1 in 2005, H. Moser & Cie is once again revolutionising the perpetual calendar in 2021, innovating the movement and showcasing it in an updated contemporary casing. A true fusion of two icons, the Streamliner Perpetual Calendar marries the simplistic elegance of the Streamliner collection and the understated ingenuity of the new calibre.

As with the other watches in the 2020-launched collection, the Streamliner Perpetual Calendar has perfectly rounded curves, a nod to the collection’s namesake – the sleek high-speed locomotive designs of the 1920s and 1930s. These curves are echoed in the design of the integrated steel bracelet that is elegantly arced to follow the line of the wrist.

The watch is equipped with a 42.3 mm steel cushion case, water-resistant to 12 ATM, with alternating brushed and polished surfaces, as well as hollowed and satin-finished forms on the sides, recalling the traditional unusual shapes typical of Moser cases. A sunray brushed finish adorns its bezel. The case is topped by a subtly domed Glassbox type sapphire crystal. Via its see-through Sapphire case-back, the HMC 812 calibre is plain to see and admire. 

Bearing the same advantages as the HMC 341 calibre, the HMC 812 is fitted with a direct-drive central seconds hand. The HMC 812 uses the indices to indicate the months, with a small red and white central hand directing attentions to them, while its leap year indicator is placed on the movement side. The brand’s signature fumé dial, seemingly nearly bare at first glance, in actuality packs a multitude of functions.

The red and white outer minute track around the dial’s edge measures the movement of the central seconds hand. The three-dimensional curved hands indicating the hours and minutes are formed of two sections and feature inserts made from Globolight®, an innovative ceramic-based material containing Super-LumiNova®. The seconds hand, the power reserve hand and the months hand bring to mind the ones on the dials of measuring instruments or car dashboards. 

Displayed at 10 o’clock on the dial is the indicator for the watch’s 168-hour power reserve, while at 4 o’clock, a window showcases the date – its large format unmissable, a feature enabled by two superimposed discs that operate one after the other, from 1 to 15 then from 16 to 31. The numerals are tilted to 26° as the date window, aligned on the crown, is positioned at an unusual angle.

At midnight, the date changes in a flash, due to the “Flash Calendar” instantaneous date-change mechanism. The traditional Moser double horizontals stripes and an anthracite grey PVD coating on the balance bridges, train wheels, barrel and escapement plate, as well as a microblasted main plate that features anthracite rhodium plating, lend the HMC 812 calibre an ultra-contemporary finish.

This cover story appears in our 2021 annual watch supplement, Cachet. Read the full magazine today on Magzter.