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Armin strom sets the tone in the realm of transparent mechanics with the Gravity Equal Force Ultimate Sapphire Purple

MAY 06 2024    |    Novelties

Armin Strom fuses masterful mechanics with a bold chromatic twist, unveiling its latest Ultimate Sapphire Edition. The iconic Gravity Equal Force now sports a striking purple guilloché-engraved mainplate by Kari Voutilainen. 

Armin Strom’s System 78 collection represents the independent manufacture’s purest expression of innovative haute horlogerie. Within it, the classical codes of watchmaking are revisited to bring about new functions and solutions, while also expressing the brand’s unique aesthetic sensibilities. With an emphasis on transparency, as well as highlighting kinetic elements, the Gravity Equal Force stands out as a technical tour-de-force with an instantly recognisable look – outstanding in form and function, finished by meticulous hand decoration. Now, with the new ‘Purple’ Ultimate Sapphire Edition, Armin Strom is doubling down on integrating vibrant chromatic hues with exceptional mechanics.

Let it reign: Gravity Equal Force Purple

At once regal and electric, the latest edition of the Gravity Equal Force features a colour Armin Strom has never used before. Its base plate boasts a guilloché engraved motif with a barley grain pattern, expertly handcrafted in the atelier of acclaimed independent watchmaker Kari Voutilainen using a traditional rose engine lathe. The striking purple colour is applied using a 3D PVD process, which reflects a wide spectrum of tones as it shifts with the light. Making this edition even more outstanding, the small off-centred dial is crafted from transparent sapphire crystal, which is reserved exclusively for the Gravity Equal Force’s Ultimate Sapphire Editions. The crowning glory is a light grey nubuck leather strap with purple stitching and keepers. The Gravity Equal Force Ultimate Sapphire Purple is limited to a run of 25 pieces per year.

 

Automatic: redefined

The Gravity Equal Force stands out as the first automatic watch endowed with an equal force transmission integrated directly in the mainspring barrel - a patented mechanism by Armin Strom. It provides consistent power transmission to the regulating organ, ensuring unwavering precision throughout the watch’s autonomy. The power reserve indicator forms part of the barrel, which is entirely visible from the dial side, opposite the micro-rotor with a unique click system featuring two springs for better winding efficiency.

Also this latest creation, part of Armin Strom’s perpetual quest for superior chronometric performance, was entirely developed, manufactured and decorated within the walls of the Bienne-based manufacturing site. Like all Armin Strom watches, the Gravity Equal Force Purple’s movement is assembled a first time to ensure it is in perfect working order and that it meets the brand’s exacting decorative standards, then taken apart and assembled a second time when it is ready to be cased in its final form. 

 

Putting the ‘haute’ in ‘horlogerie’

What separates a mere tool from a work of art is craftsmanship. Like a canvas for artistic expression, superlative hand-finishing applied by specialised watchmakers and seasoned artisans can be appreciated throughout the Gravity Equal Force and its many proudly exposed layers and components. Polished bevels (anglage) on the bridges, black polished screws, polished countersinks, perlage and various types of graining, be it straight or circular, as well as Geneva stripes on the three-quarter bridge visible through the case’s back.

One of the Gravity Equal Force’s most distinctive elements is the triplet of dark grey ruthenium-plated bridges that occupy the right-hand portion of the open display. Inspired by the finger-style bridges found in pocket watches, it takes up to an entire day for these bridges to be embellished by hand. First, the undersides are given a matt finish, after which the sides are given a straight-graining finish by carefully sliding them on an abrasive paper to produce continuous, shimmering fine lines. Then, the inner and outer chamfers of the bridges are bevelled with increasingly fine files and then finished with a flash polish using locally sourced gentian wood to remove even the finest lines. Finally, a straight-graining finish is applied to the top side for ultimate radiance.

Armin Strom : 15 years in the science of movement

In 2008, longtime friends and partners Serge Michel and Claude Greisler took the reins at Armin Strom and founded its very own manufacture in the watchmaking town of Biel in 2009. Just one year later, the duo presented their very first watch with a movement designed and manufactured in-house. Over the following years, Armin Strom would become a truly integrated and self-sufficient manufacture, creating 17 exclusive calibres and developing several world firsts in the domain of watchmaking. In 2016, it introduced the Mirrored Force Resonance, a game-changing resonating dual regulator developed for maximum chronometric precision with a captivating oscillation mechanism on the dial-side of the watch. In 2019, Armin Strom reinvented the automatic watch movement with the Gravity Equal Force, the first automatic watch to feature an equal force transmission mechanism within the barrel that had previously been found only in pocket watches. Today, Armin Strom stands out as a leading force of creative, independent watchmaking, with its own distinct design language and exceptional attention to detail highlighted by hand-finishing all its creations. 2024 promises to be a year full of surprises, and the best is yet to come…

 

Gravity Equal Force Ultimate Sapphire Purple

Technical specifications

                   

Indications     Hours, minutes, seconds, power reserve indicator
Movement     Armin Strom manufacture Caliber ASB19
      Automatic winding with micro rotor, Geneva-drive equal force barrel, offset display with subdial seconds
Main plate   purple PVD plate with guilloché pattern by Kari Voutilainen
Regulating system   Balance wheel with 4 regulating screws
Power reserve   Geneva stop-work limited to 72 hours
Dimensions   35.52 mm x 11.67 mm
Frequency   3,5 Hz (25,200 vph)
Finishing   Hand-finishing to the highest quality level
Jewels   28
Number of components   202
Case   stainless steel
    Sapphire crystal and case back with anti-reflective treatment
Diameter   41 mm
Height   12.65 mm
Water resistance   3ATM
Lug-to-Lug   48.09 mm
     

Dial

 

Grey toned off-center sapphire dial with subdial

Hands  

Faceted polished hands and Super-LumiNova® filling

Strap   Delivered with a grey nubuck leather strap with purple stitching and keepers
Width lugs/buckle   20/18 mm
Buckle   Pin buckle or folding clasp available in stainless
Reference   ST24-GEF.SA.AC.M.A7.FC
Limited production   25 pieces per year

 

 

                                           

                                            

 


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JANUARY 19 2026    |    Novelties

DANIEL ROTH Unveils the Extra Plat Rose Gold Skeleton

A contemporary expression of classical proportion, revealing the architecture of high watchmaking
 

DANIEL ROTH presents the Extra Plat Rose Gold Skeleton, a new interpretation of one of the Maison’s most emblematic creations. Remaining faithful to the proportions and restrained elegance of the Extra Plat, this latest iteration introduces skeletonisation for the first time in the brand’s modern revival, allowing the inner architecture of the watch to take centre stage.

Conceived in the spirit of La Montre Objet d’Art, the Extra Plat Rose Gold Skeleton preserves the calm geometry of the double‑ellipse case while offering a transparent view into the movement, transforming technical construction into a visual and artistic experience.

The Extra Plat: A signature revisited
Simplicity, when executed with absolute precision, has long been central to the identity of DANIEL ROTH. During the early years of his independent career, Mr. Roth considered the Extra Plat a complication in its own right, favouring it for the technical discipline required to achieve true thinness and perfect proportion.

Defined by its double‑ellipse case and balanced architecture, the Extra Plat became a cornerstone of the Maison’s aesthetic vocabulary in the early 1990s. While Daniel Roth produced skeletonised versions of select complications during that period, the Extra Plat itself was never skeletonised. This new creation therefore marks a respectful yet meaningful evolution, expanding the expressive range of the Extra Plat while remaining faithful to its original spirit.

The DR002SR calibre: a skeletonised rose gold heart
At the centre of the Extra Plat Rose Gold Skeleton is the new manually wound calibre DR002SR, developed and manufactured entirely at La Fabrique du Temps Louis Vuitton under the supervision of master watchmakers Michel Navas and Enrico Barbasini.

Based on the DR002, the DR002SR has been re‑engineered from the ground up specifically for skeletonisation. The bridges and plates have been reshaped to maximise openness and visual clarity, while preserving structural rigidity and chronometric performance. Crafted in solid 18k 5N rose gold, the movement mirrors the warmth of the case and provides an ideal canvas for traditional hand finishing.


Transparency in motion
Skeletonisation is an exercise in reduction and balance. With the DR002SR, DANIEL ROTH brings this principle to its highest expression. The calibre reveals a wealth of hand‑executed details, including numerous hand‑polished internal angles, black‑polished steel components, and meticulously bevelled bridges—finishes that can only be achieved by skilled artisans and never by machine.

Despite its openworked construction, the DR002SR retains a power reserve of 65 hours and a frequency of 4 Hz, underscoring the Maison’s commitment to both technical integrity and timeless aesthetics.


Slim proportions, uncompromised structure
Housed in a 38.6 × 35.5 mm double‑ellipse case crafted in 18k rose gold, the Extra Plat Rose Gold Skeleton measures just 6.9 mm in thickness. This exceptional slenderness ensures that the watch remains true to the Extra Plat philosophy of discreet elegance and effortless wearability.

Produced in extremely limited numbers each year, the Extra Plat Rose Gold Skeleton is intended for collectors who value traditional high watchmaking expressed with clarity, restraint, and depth.

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