Shopping Cart

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

 

 

                                           

                                            

 


Related Articles

MARCH 17 2026    |    Novelties

Reinventing the Rhythm of Time: Dominique Renaud Presents the Pulse60

Haute Horlogerie Dominique Renaud (HHDR) marks its official debut with the launch of the Pulse60, unveiled in preview at the Time To Watches fair in Geneva (April 14–19, 2026). This first creation of the new Dominique Renaud brand introduces a radical approach to low‑frequency mechanical watchmaking and expresses the purest form of Renaud’s watchmaking philosophy.

A Vision Rooted in First Principles
Dominique Renaud, co‑founder of the legendary Renaud & Papi manufacture and creator of numerous landmark complications, returns with a renewed focus on foundational movement principles. Guided by the maxim “form ever follows function,” his work embraces clarity, purity and a minimalist, self‑evident aesthetic.
The establishment of HHDR in Tolochenaz brings together a team of watchmakers, designers and engineers in a collaborative, idea‑driven environment. HHDR is conceived as a living laboratory — a place where experimentation, shared expertise and long‑term exploration shape new forms of contemporary horology.

Pulse60 — A New Mechanical Language
At the heart of the Pulse60 is the newly developed BUA2024 movement, which embraces an ultra‑low 1 Hz frequency — just one oscillation per second, echoing the natural rhythm of the human heart. This approach reduces escapement shocks and disturbances, transforming time measurement into a slower, more embodied rhythm.


To master this low frequency, the movement features a monumental 20 mm high‑inertia balance wheel, inspired by marine chronometers. Its large moment of inertia stabilizes the rate by absorbing minute variations in energy and motion.

Dominique Renaud has also completely reimagined the regulating organ, allowing amplitude greater than 360° without knocking, with a theoretical range reaching approximately 700°. This unprecedented freedom greatly improves static rate stability by allowing the balance to follow its own natural dynamics over a longer portion of its oscillation.

 

A Design That Expresses Its Mechanics
The Pulse60’s innovative mechanics are reflected in its seamless, fluid architecture:

- A domed crystal with no bezel
- Lug‑less construction and integrated strap
- Three‑part case structure
- Diamond‑cut or guilloché dial details
- A patented offset regulation system placed outside the balance wheel, offering a completely unobstructed view of the slow‑beating 1 Hz oscillator

The display includes an hour‑minute dial at 12 o’clock, a natural dead half‑second at 9 o’clock, and a torque indicator at 3 o’clock. The caseback reveals a minimalist composition of circular and linear forms, framing the openworked escapement line and double‑roller assembly.

View Watch Gallery  
  Image 2 Image 3  Image 4  Image 5    
View More
APRIL 01 2025    |    Watches and Wonders 2025

Armin Strom Introduces The One Week Skeleton

The Armin Strom One Week Titanium Skeleton, an openworked masterpiece now fully skeletonized to reveal the intricate heart of its mechanics, combines striking design with precision engineering. Encased in lightweight titanium grade 5, it balances strength with comfort, providing a feeling of lightness that makes it easy to wear all week long.

The Armin Strom One Week Titanium Skeleton is a showcase of skeletonization, a technique that is rooted in Mr. Armin Strom’s philosophy and heritage. He sought to enhance depth and three-dimensionality while avoiding see-through to maintain elegance.

The 2023 One Week was already openworked by nature, but this version goes even further, removing more material to highlight the movement’s complexity. Few watches combine openworking and skeletonization at this level. The small seconds dial is skeletonized, revealing the power reserve level and the escapement wheel for a 3D mechanical animation. The mainplate and the barrels are also skeletonized enhancing aesthetics. Thanks to this skeletonization, the power reserve indicator is highlighted as well as the cone mechanism, reminiscent of ancient pocket watches. A major highlight is the case back, offering a mesmerizing view of the entire mechanism.

With a 7-day power reserve, this watch keeps time accurate for an entire week without needing winding. The hand-finished details reflect the level of craftsmanship behind its design. Limited to 100 pieces, the One Week Titanium Skeleton offers a refined, functional timepiece that blends robustness and comfort in a minimalist package.
 

View More
OCTOBER 02 2025    |    Novelties

Moritz Grossmann Presents the New BENU Power Reserve: Tradition Refined

Moritz Grossmann, the independent Saxon manufacture celebrated for its uncompromising craftsmanship and technical ingenuity, introduces the latest evolution of its iconic BENU Power Reserve. This new interpretation embodies the brand’s guiding principle: progress in harmony with tradition.

A Dial That Captures Light and Time
The dial is the face of a watch — a canvas where heritage meets artistry. For the first time, the BENU Power Reserve combines its signature linear power reserve indicator with Azurage decoration. This intricate guilloché pattern of ultra-fine concentric grooves animates the outer chapter ring, creating a captivating interplay of light. The softly textured matte center in shimmering argenté silver contrasts with applied blue numerals and indices, while the brand logo and minute track appear in understated grey.

Completing this refined composition are newly designed hands, handcrafted from steel in the Glashütte atelier. Each hand is meticulously beveled, polished, and then heat-blued using traditional thermal treatment. Their elegant curvature and needle-fine tips exemplify the precision and artistry that define Moritz Grossmann.

The Poetry of Mechanics: Power Reserve Indicator
Mechanical timepieces invite interaction, and the power reserve display is a charming expression of this dialogue. Positioned beneath 12 o’clock, the linear indicator reveals a two-tone bar driven by a differential gear train. When fully wound, the bar appears white; as energy diminishes, a blue segment gradually advances — a subtle yet constant reminder of the living mechanism on the wrist.

Inside the Case: Calibre 100.2
At the heart of the BENU Power Reserve beats the Calibre 100.2, an evolution of the manufacture’s foundational movement. This hand-wound calibre incorporates a differential mechanism for the power reserve display and features the brand’s signature innovations: manual winding with a pusher, a cantilevered balance cock with micrometer screw adjustment, and a separately removable winding module. Through the sapphire crystal back, the movement reveals its artistry — broad Glashütte ribbing, hand-engraved cocks, and raised gold chatons secured by blued screws.

Classic Elegance in Every Detail
The BENU Power Reserve is offered in rose gold and white gold, each with a 41 mm case that reflects the brand’s commitment to timeless proportions. The case surfaces are finely brushed to a soft matte sheen, complemented by a cross-grooved crown and slender lugs. A grey hand-stitched leather strap with blue stitching echoes the dial’s accents, completing a harmonious design that speaks to connoisseurs of understated luxury.

A Legacy Reimagined
Founded in 1854 by visionary watchmaker Moritz Grossmann, the Glashütte tradition was revived in 2008 by master watchmaker Christine Hutter. Today, the manufactory continues to honor its heritage through innovation, artisanal excellence, and a dedication to the finest German craftsmanship.

 

View Watch Gallery
Image 1 Image 2Image 3 Image 4Image 5
View More
JUNE 23 2026    |    Novelties

Arnold & Son Unveils the Perpetual Moon 41.5 Steel "Colours of the Moon"

Arnold & Son has unveiled its new "Perpetual Moon 41.5 Steel Colours of the Moon" collection, a series of highly exclusive, limited-edition timepieces inspired by the changing celestial hues of Earth's natural satellite. Detailed in the official release document, "ENG_A&S PM 41.5 Steel Colours of the Moon.doc", the collection features three distinct versions—the Blue Moon, Golden Moon, and Red Moon—each celebrating a unique atmospheric or seasonal phenomenon that alters the Moon's appearance and has fascinated civilisations throughout history.

Reinterpreting the iconic Perpetual Moon collection, these new models introduce a 41.5 mm stainless-steel case that balances horological exclusivity with everyday versatility. In a watchmaking first, Arnold & Son has applied a pioneering Physical Vapour Deposition (PVD) treatment directly onto precious mother-of-pearl. This innovative process creates deep, shifting reflections across the dials and moon-phase skies, showcasing the natural organic layers of the material with patterns that recall the flowing grain of Damascus steel.

The astronomical precision of the moon phase is enhanced by Super-LumiNova hidden beneath the colored mother-of-pearl moon disc, accompanied by hand-painted luminescent constellations of Cassiopeia and Ursa Major—a poetic tribute to historical mariners who relied on them for navigation. Bringing this celestial mechanics to life is the in-house A&S1512 manual-winding calibre. This movement provides a generous 90-hour power reserve and displays meticulous luxury finishes, including radiating Côtes de Genève and a secondary moon-phase indicator, all visible through the sapphire crystal case back.

Each of the three references is paired with a matching hand-stitched alligator leather strap and secured with a stainless-steel pin buckle. To maintain their extreme exclusivity, production is strictly limited to just 18 pieces per version.

 

View Watch Gallery
Angelus Instrument de Mesures

Angelus Instrument de Mesures

Angelus Instrument de Mesures

Angelus Instrument de Mesures
View More
OCTOBER 07 2025    |    Novelties

A Week in Blue: The One Week Manufacture Edition Blue

Armin Strom unveils the One Week Manufacture Edition Blue, a bold evolution of its foundational calibre, now reimagined in a striking deep blue. Limited to just 100 pieces, this timepiece reflects the brand’s dedication to mechanical artistry and uncompromising craftsmanship.

A Sculptural Expression of Precision
Encased in a 41 mm stainless steel case and paired with an integrated steel bracelet, the watch features a fully openworked architecture. The traditional dial is replaced by a blue PVD-coated mainplate, creating a vivid stage for the movement’s choreography. Every component is arranged in perfect symmetry, emphasizing depth, contrast, and clarity.

Engineered for Endurance
At its core is the manual-winding Calibre ARM21, developed and assembled entirely in-house. With dual barrels in series, it delivers a full seven-day power reserve and operates at 3.5 Hz for enhanced stability. A standout feature is the three-dimensional power reserve indicator, driven by a conical gear and polished cone — a nod to traditional pocket watches.

Each movement is hand-finished to haute horlogerie standards, with Geneva stripes, polished bevels, and chamfered edges. Every piece is assembled twice, ensuring flawless performance and visual harmony.

View Watch Gallery
Image 1 Image 2  
View More
ENDLESS DISCOVERY IN YOUR INBOX
Join our mailing list to receive insider updates on our latest collections, invites to private events, and other personalized offerings.