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

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
JUNE 10 2025    |    Novelties

Arnold & Son Nebula 40 Steel, Blue Edition Design Philosophy: Radiating Harmony

The watch features a star-shaped arrangement of seven bridges, radiating from the center like a nebula, giving it both structural integrity and visual depth.

The movement is laid out with four lines of symmetry, aligning the barrels, balance, and small seconds for a harmonious aesthetic.

Technical Excellence: A&S5201 Calibre

Dual barrels provide an impressive 90-hour power reserve.

Components are arranged in a kinematic chain around the edge, enhancing both function and form.

The crown mechanism is inverted and placed on the case-back side for symmetry with the first wheel at 9 o’clock.

Aesthetic Details

The lower levels of the movement are treated with a rich blue PVD, contrasted by palladium-finished bridges and components.

Includes horizontal satin brushing on the dial side and Arnold & Son’s signature ‘Rayons de la Gloire’ motif on the reverse.

The 40 mm diameter and 9.10 mm thickness ensure elegance on the wrist.

Strap & Bracelet Options

Available with a blue alligator leather or rubber strap.

Also offered with a three-link steel bracelet that highlights the watch’s symmetry and skeletonized beauty.

View Watch Gallery
Image 1 Image 2 Image 3 Image 4
View More
JULY 15 2026    |    Novelties

A New Pulse of Colour: Armin Strom Unveils the Mirrored Force Resonance Red

Armin Strom has masterfully fused its revolutionary resonance technology with a bold, contemporary aesthetic in the new Mirrored Force Resonance Red. Limited to just 15 pieces worldwide, this rare masterpiece introduces a striking off-centre guilloché dial in vibrant red. By pairing traditional hand-crafted artistry with the brand’s signature open-worked design, this timepiece breathes dynamic new energy into Armin Strom's celebrated dual-balance mechanism, creating a captivating dialogue between classic hand-finishing and cutting-edge mechanical architecture.

The brilliant red dial is hand-crafted on a traditional, manually operated rose engine lathe, engraving a radiating pattern that catches and plays with light in captivating reflections. Encircled by black azuré (蝸形紋) chapter rings and topped with faceted, floating index markers, the dial's layout creates a stark, three-dimensional contrast that maximizes both visual depth and legibility. Housed in a polished 43 mm stainless steel case, the movement's technical architecture is framed by anthracite-coated bridges and paired with a dark grey Alcantara strap—ensuring that the vibrant red dial and the synchronized dance of the resonance mechanism remain the undisputed center of attention.

At the heart of this technical marvel lies the in-house Calibre ARF21, a hand-wound movement that integrates two completely independent movements within a single calibre. Connected via Armin Strom's patented Resonance Clutch, the two opposing balance wheels transfer vibrations to enter and maintain a perfect state of harmonic resonance. This physical synchronization significantly improves chronometric stability and rate consistency over time. To let wearers witness this horological phenomenon in action, a pusher at 2 o'clock activates a flyback mechanism, resetting both independent seconds hands to zero simultaneously so their perfect synchrony can be monitored in real-time.

Every millimeter of the Mirrored Force Resonance Red showcases Armin Strom's uncompromising dedication to haute horology standards, featuring meticulous hand-polished bevels, perlage, circular graining, and mirror-black polished screws. On the reverse side, the main plate features technical inscriptions rendered in three-dimensional relief, rising directly from the metal's surface. As is tradition for the Swiss manufacture, each watch is assembled twice to guarantee absolute precision. For collectors seeking the pinnacle of independent Swiss watchmaking, this 15-piece limited edition represents a perfect harmony of mechanical science and artistic expression.

 

View Watch Gallery
Image 1






  

 

View More
FEBRUARY 13 2026    |    Novelties

Armin Strom Unveils the Dual Time GMT Resonance Rose Gold

Armin Strom presents a refined and visually striking evolution of its celebrated Dual Time GMT Resonance collection with the debut of the Dual Time GMT Resonance Rose Gold. Rendered for the first time in a 39 mm 18K rose‑gold case, the timepiece introduces a warm and elegant reinterpretation of the brand’s technically driven design language. Limited to 50 pieces worldwide, this edition pairs the Maison’s signature resonance innovation with a rich new aesthetic personality, blending contemporary elegance with mechanical sophistication.

A New Expression of Design & Craftsmanship
The new Rose Gold edition distinguishes itself through its interplay of warm tones and finely executed textures. The 18K rose‑gold case forms a glowing frame around the black‑gold grenage dial, a surface enriched by depth, contrast, and granular refinement. The dial’s twin layouts—each dedicated to one time zone—are clearly defined by black azurage chapter rings, ensuring intuitive reading while maintaining the balanced symmetry that defines the Resonance line. The rose‑gold‑coloured, faceted and polished hands, together with matching applied indexes, elevate the aesthetic with a luxurious brightness. At six o’clock on each sub‑dial, polished and blackened steel sun-and-moon day/night discs add functional clarity and a poetic visual touch. Completing the ensemble is a matte anthracite alligator strap accented with grey stitching and secured with a matching 18K rose‑gold pin buckle, creating a cohesive, modern, and refined profile.

The Science of Movement: Calibre ARF22
At the heart of the watch lies Armin Strom’s hand‑wound, in‑house Calibre ARF22, a movement defined by the brand’s patented resonance clutch system. This mechanism couples two independent balance wheels and allows them to synchronise through resonance, a natural physical phenomenon that enhances chronometric stability. What might otherwise remain a theoretical curiosity is transformed into a practical complication: each regulating organ governs its own time display, enabling two entirely independent time zones. Each dial also features a corresponding day/night indicator, making the watch particularly intuitive for world travellers. Operating at 3.5 Hz (25,200 vph) and offering a 42‑hour power reserve, the ARF22 movement brings a dynamic, kinetic quality to the dial, where the twin oscillators interact in real time. The aesthetic presentation of the movement reflects haute horlogerie values, with meticulous hand‑polished bevels, black‑polished steel components, circular graining, perlage, and Côtes de Genève on full display through sapphire crystals on both sides. In keeping with Armin Strom tradition, each watch is assembled twice, ensuring uncompromising mechanical integrity and flawless finishing.

The new Dual Time GMT Resonance Rose Gold is offered in a strictly limited edition of 50 pieces

 

View Watch Gallery
Image 1






  
View More
APRIL 29 2026    |    Novelties

A Splash of Fresh Green: Moritz Grossmann Debuts the TEFNUT Silver-Plated by Friction Anniversary Watch

The year 2026 marks a historic milestone for the Moritz Grossmann manufactory in Glashütte, as it celebrates the 200th birthday of its visionary founder and namesake, born on March 27, 1826. A genius watchmaker, scientist, author, and initiator of the German Watchmaking School, Grossmann profoundly shaped the craft of horology and the fate of his hometown. Rather than merely imitating historical concepts, the modern manufactory honors his legacy by blending his cutting-edge philosophy with modern engineering. This dedication to technological perfection and exceptional aesthetics cements its place among the world's elite elite watchmakers.

To commemorate this bicentennial occasion, the brand has unveiled its third anniversary special edition: the TEFNUT Silver-Plated by Friction. Debuting on April 29, 2026, this launch presents an exclusive premiere for collectors—the very first time that the sleek TEFNUT model is made available in a stunning 750/000 yellow gold case, alongside a 750/000 white gold version. Both variations pay homage to their heritage by incorporating an "1826" engraving on the balance cock and showcasing a vintage 1875 "M. GROSSMANN" logo on the dial.

At the heart of the timepiece lies the ultra-flat manufactory calibre 102.1, a hand-wound movement measuring just 4 mm in height and 26 mm in diameter. This compact footprint enables the watch to retain its remarkably elegant, low-profile silhouette. The calibre embodies classic Grossmann pillar movement architecture with a 3/5 plate, incorporating his signature raised gold chatons, an optimized mainspring barrel with bilateral jewel bearings, and a stepped balance cock with a micrometer screw. Each component is meticulously hand-finished to ensure absolute technical and visual distinctiveness.

The defining aesthetic feature of this model is its striking dial, which boasts a rare "silver-plated by friction" finish. Executed entirely by hand in the brand's ateliers, a master artisan brushes a specialized paste of silver powder, salt, cream of tartar, and water onto the brass surface to create a velvety, fine-grained texture that beautifully diffuses light. To provide a contemporary contrast, the numerals, minute scale, and historic logo are rendered in a vibrant green hue. Hovering above are extraordinarily fine, hand-crafted lance-shaped hands, polished in gold for the yellow gold model and annealed to a brown-violet tone for the white gold edition. Each variation is strictly limited to just 12 pieces worldwide.

View Watch Gallery  
Image 1  Image 2 Image 3  Image 4       
View More
MARCH 02 2026    |    Novelties

Introducing the Armin Strom Mirrored Force Resonance Ruby

ARMIN STROM introduces a compelling new interpretation of its most emblematic complication with the debut of the Mirrored Force Resonance Ruby. This creation stands out through its extraordinary natural ruby dial, sourced and crafted by a local Swiss stone artisan. The brand selected only genuine ruby exhibiting depth of colour, fine inclusions, and naturally occurring variations—features that are not flaws but signatures of authenticity, shaped by geological processes over millions of years. As light moves across the dial, subtle tonal shifts appear, infusing the watch with a vibrant mineral presence that contrasts strikingly with the symmetry and modernity of the exposed mechanics.

Beyond its visual impact, this edition embodies ARMIN STROM’s belief that materials must carry meaning. While natural ruby asserts its aesthetic and symbolic presence on the dial, synthetic ruby jewels within the movement fulfil their longstanding horological role of reducing friction and ensuring long-term precision. It is a thoughtful dialogue between nature and engineering, where raw mineral beauty coexists with technical necessity.

At the core of the watch lies the hand-finished Calibre ARF21, a manufacture movement entirely designed and produced in-house. Its defining feature is the brand’s patented Resonance Clutch Spring, which connects two independent regulating systems, enabling the balance wheels to oscillate in harmonic resonance. This phenomenon enhances chronometric stability and is visually showcased by a pusher at 2 o’clock that resets both seconds hands simultaneously—a dramatic demonstration of mechanical synchronicity in action. Operating at 3.5 Hz (25,200 vph) and offering a 48-hour power reserve, the movement transforms a centuries-old scientific principle into contemporary watchmaking mastery.

Craftsmanship remains central to ARMIN STROM’s ethos. The bridges feature hand-polished bevels, black-polished screws, perlage, and circular graining, with Geneva stripes enriching the reverse side. As with every ARMIN STROM timepiece, each watch is assembled twice, ensuring absolute performance and finishing quality. This meticulous approach, combined with the vibrant ruby dial, creates a visually dynamic composition—a living interplay between stone, metal, and motion.

Encased in a 43 mm stainless steel case and fitted with a grey Alcantara strap featuring white stitching, the Mirrored Force Resonance Ruby delivers both presence and refinement. It is not merely a new dial variation, but an artistic expression grounded in horological integrity—an encounter between natural geology and mechanical resonance, distilled into a timepiece of exceptional character.

 

View Watch Gallery
Image 1


  
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.