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

JUNE 11 2026    |    Novelties

Angelus Instrument de Mesures: Triple Scale Monopusher Chronograph

Angelus unites the chronograph's key functional scales—telemeter, pulsometer, and tachymeter—in a single design. True to its heritage as a maker of functional timepieces, Angelus brings together the expertise developed through its previous instruments in the Instrument de Mesures. Produced in two limited editions of 25 pieces, this watch is a genuine instrument of measurement, designed to calculate elapsed time, the speed of sound, distance travelled and heart rate. Using a single chronograph hand, it integrates three functions, each with its own dedicated scale. Housed in a 39 mm steel case, its three-dimensional dial is both highly legible and meticulously graduated, giving the Instrument de Mesures the character of an authentic tool watch with a distinctive vintage charm and singular identity.

One Instrument, Multiple Measurements
Integrating these three scales alongside the essential minute track required a particularly sophisticated design approach. The amount of information to be displayed, combined with the need for legibility and clarity, led Angelus to adopt a distinct colour code for each function. This arrangement is reinforced by a three-dimensional dial construction, featuring a domed centre and outer edge connected by a sloping intermediate section. The telemetric scale is situated on the highest level at the periphery of the dial. The pulsometer extends across the angled intermediate section, and the tachymeter, in the form of a spiral, is located closest to the hands.

The In-House A5000 Chronograph Calibre
The Instrument de Mesures is powered by Angelus's in-house A5000 chronograph calibre. Its classical architecture showcases numerous intricately shaped components, providing an ideal canvas for high-end finishing. Faithful to the great traditions of chronograph watchmaking, the A5000 incorporates a column wheel and a horizontal clutch, both defining features of traditional chronographs.

 

View Watch Gallery
Angelus Instrument de Mesures

Angelus Instrument de Mesures

Angelus Instrument de Mesures

Angelus Instrument de Mesures
View More
NOVEMBER 19 2025    |    Novelties

A Deeper Cut: Armin Strom One Week Skeleton Rose Gold

   

Armin Strom extends its golden era with the One Week Skeleton Rose Gold, a new interpretation of its architectural One Week design. This fully skeletonised masterpiece reveals the depths of its mechanics, paying tribute to Mr. Armin Strom’s pioneering artistry in skeletonisation—a craft at the heart of the brand’s philosophy and heritage.

For the first time, the in-house calibre appears in a solid 18K rose gold case, enriching the collection with a warmer character. Rose gold-coloured finger bridges, hands, and applied indexes mirror the tone of the case, while a sleek black textile strap provides a refined modern contrast. Measuring 41 mm in diameter, the case remains compact and ergonomic, while its skeletonised architecture gives the watch a distinctive presence—a harmonious balance of technical craftsmanship and precious metal elegance.

Seven Days of Precision
At its heart lies the hand-wound Calibre ARM21-S, a reinterpretation of Armin Strom’s first in-house calibre. Two mainspring barrels work in series to deliver a steady flow of energy for seven days, wound by two ratchet wheels visible on the dial side—a distinctive Armin Strom signature. Operating at 3.5 Hz, the calibre ensures consistent precision and stability in daily wear.

Inspired by historical pocket watches, the conical power reserve mechanism is complemented by a 3D power reserve indicator, displaying remaining energy with exceptional clarity. Central hours and minutes keep the display symmetrical, while a skeletonised small seconds at 9 o’clock adds an engaging sense of motion.

Transparency in Gold
Every component of the Calibre ARM21-S is decorated by hand, reflecting Armin Strom’s dedication to traditional craftsmanship. Hand-polished bevels, Geneva stripes, circular graining, and finely finished screw sinks demonstrate uncompromising attention to detail. Each One Week is assembled twice—a hallmark of the brand’s commitment to mechanical precision and aesthetic integrity.

Limited to just 50 pieces worldwide, the One Week Skeleton Rose Gold continues Armin Strom’s modern gold chapter—a celebration of mechanical transparency, precision, and craft.

View Watch Gallery
Image 1  Image 2  Image 3 
View More
SEPTEMBER 19 2025    |    Novelties

Armin Strom Unveils the Tribute 1 Green: A Celebration of Nature’s Elegance

Armin Strom introduces the Tribute 1 Green, a refined dress watch that pays homage to the timeless beauty of nature. Limited to just 50 pieces, this new release brings forest-inspired tones to the brand’s most elegant collection, combining artisanal craftsmanship with modern mechanical innovation.

A Forest-Inspired Masterpiece

The Tribute 1 Green features a striking off-centre dial in forest green, adorned with a hand-engraved grain d’orge guilloché pattern and crisp white Roman numerals. A frosted subdial adds depth and texture, while the green Alcantara leather strap with off-white stitching completes the composition with understated sophistication. The openworked motor barrel, secured by a polished finger bridge in stainless steel, echoes the case design and showcases Armin Strom’s signature fusion of symmetry and mechanical artistry. The 38 mm stainless steel case, with anti-reflective sapphire crystals front and back, ensures optimal clarity and elegance.

Exceptional Performance

At the heart of the Tribute 1 Green is the manual-winding Manufacture Caliber AMW21, offering an impressive 100-hour power reserve. This is made possible by the brand’s patented equal force barrel, designed for efficiency and compactness. Operating at 25,200 vibrations per hour (3.5 Hz), the movement reflects Armin Strom’s technical mastery, with 97% of components produced in-house.

Haute Horlogerie, Hand-Finished

Every Tribute 1 Green is a testament to traditional watchmaking. The case features brushed and polished surfaces, finished entirely by hand. Inside, the movement is decorated with Geneva stripes, circular graining, and a mirror-polished finger bridge, all executed by Armin Strom’s skilled artisans.

True to the brand’s commitment to excellence, each watch is assembled twice—once for mechanical precision and again after decoration—to ensure the highest standards of performance and aesthetics.  

View Watch Gallery
Image 1 Image 2  
View More
MARCH 17 2026    |    Novelties

Greubel Forsey Unveils Final Editions of the Balancier Convexe S² in White and Black Ceramic

Greubel Forsey introduces the final and most exclusive editions of the Balancier Convexe S²: one in black ceramic with 5N red gold, and one in white ceramic, each strictly limited to 11 pieces.
These editions conclude a calibre developed through five years of mechanical and architectural exploration, with production set to cease permanently in 2026.

The Convexe case (41.5 mm) and movement were conceived as a single architectural whole, integrating Greubel Forsey’s signature 30° inclined balance wheel system as the visual and chronometric centre. The openworked movement features 301 components, including a 68‑part escapement platform, and is 
powered by two rapid-rotation coaxial barrels delivering a 72‑hour chronometric reserve.

Finishing remains uncompromising: frosted titanium bridges, polished bevels, hand‑finished countersinks, and meticulous transitions — even on invisible components.

Two Final Interpretations
Black Ceramic & 5N Red Gold
A dramatic contrast of dark architecture framed by ceramic, with red gold adding warmth and sculptural depth.The interplay of matte and polished surfaces enhances the piece’s three‑dimensional form

White Ceramic
A purist, graphic expression that highlights the structural geometry of the movement through light and shadow.The monochromatic case offers clarity, openness and a distinctly technical aesthetic.

Both editions preserve the characteristic S² display: suspended hours/minutes bridge, small seconds, and sector power‑reserve indication beneath a curved sapphire crystal.

This launch marks the concluding chapter of the Balancier Convexe S²’s five‑year evolution — not an iteration, but a final statement. As of 2026, Greubel Forsey will begin a gradual shift toward an almost entirely new collection, retiring earlier calibres with intention and ceremony rather than quiet discontinuation.

 

View Watch Gallery  
Image 1  Image 2 Image 3  Image 4  Image 5  Image 6 Image 7  Image 8  
View More
JANUARY 19 2026    |    Novelties

gérald genta unveils the Geneva Time Only — sculptural elegance distilled into a 38 mm cushion‑case

The Maison gérald genta expands the Geneva collection with the Geneva Time Only, a new 38 mm creation in warm rose gold 4N and cool white gold, translating the line’s sculptural language and “l’esprit de Genève” into an essential, everyday expression.

“I wanted to capture the intuitive, instinctive genius and artistry of Mr. Genta,” says Matthieu Hegi, Artistic Director at La Fabrique du Temps Louis Vuitton, who leads the Geneva collection’s creative direction.

The updated cushion case—neither round nor square—features softened contours, a refined gadroon and a new single, broader lug on each side, striking a rare balance of daring and discretion. Light plays across polished and satin surfaces, while the collection’s signature two‑segment minute track forms a subtle optical illusion as the outer track follows the cushion silhouette and the inner ring remains perfectly circular. The grained brass dial carries a gentle fumé gradient—lighter at the center, darker at the edge—for tonal depth.

At just 8.15 mm thick, the 38 mm case slips neatly under a cuff; both models are fitted with rounded, mirror‑polished solid‑gold hands and applied indexes and tone‑on‑tone calfskin straps. Under the dial, the GG‑005P automatic calibre—Zenith Elite–based with redesigned bridges and a reworked oscillating mass—beats at 4 Hz with a 50‑hour power reserve (158 components, 27 jewels), visible through the sapphire caseback. Water‑resistance is 30 m.

View Watch Gallery
Image 1 Image 2Image 3 Image 4Image 4Image 4
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.