Armin Strom Gravity Equal Force - References, Prices and Owners' Reviews

Armin Strom Gravity Equal Force was launched in 2019 as a very “Armin Strom” answer to an old problem: a mainspring’s force is not constant, and that variation always ends up affecting rate stability. Rather than hiding the mechanics, the model brings them to the foreground with an open architecture and an off-centre time display, while introducing a constant-force barrel combined with a Geneva-style stop-work, integrated at the heart of an automatic micro-rotor winding system. The idea is not to build a “theoretical” watch, but a wearable, readable, durable piece that turns an engineering solution into a daily experience: you can see force being managed, you understand what is happening, and you enjoy a watch that stays composed even when the spring’s energy would naturally fluctuate.

Design & readability: the model’s identity

The Gravity Equal Force embraces a movement-on-the-dial aesthetic: sculptural finger bridges, a staged barrel, a visible micro-rotor, and a time display pushed onto a small off-centre dial that literally floats above the mechanical landscape. This layout creates a rare balance: the eye can admire the mechanics, yet it knows where to read the time without hesitation. In practice, the identity is not that of a minimalist watch; it is an open but structured watch, where architecture serves understanding rather than gratuitous effect.

Readability depends heavily on color and texture variants, because the model exists with different plates and treatments that change contrast between rhodium-toned components, darker finishes, and the off-centre sapphire dials. Yet the hierarchy remains stable: local time is read on the left, the seconds are separated, and the energy reserve is understood through the barrel and transmission logic. It is not a watch you “decode” in daily life, but a watch that rewards prolonged looking, thanks to a layout conceived like an instrument rather than as decoration.

Case, strap, and everyday comfort

The 41 mm steel case aims for universal wear in contemporary fine watchmaking: present enough to give depth to the dial side, yet compact enough to stay comfortable under a cuff. The stated thickness around 12.65 mm is explained by the open construction, the bridge volumes, and the micro-rotor choice, but wrist perception remains balanced thanks to curvature, bezel design, and alternating brushed and polished surfaces. In use, what stands out is sport-chic comfort without heaviness, which matters for a watch whose point is being worn often.

With stated water resistance of 3 ATM, the Gravity Equal Force sits in a “careful daily” register: office life, rain, travel, with no aquatic ambition. Strap choices (often leather or nubuck depending on editions) follow the same intention: expressive, yet easy to live with. What matters most, as always with an open watch, is stability on the wrist: if the watch shifts, the off-centre dial becomes less comfortable to read. Properly fitted, the Gravity Equal Force delivers a sense of calm precision: it disappears physically while remaining visually captivating.

Movement: architecture, performance, and servicing

The ASB19 calibre is the backbone of the concept: an automatic with micro-rotor, designed to keep a relatively compact silhouette while leaving the mechanics widely visible. Its 25,200 vph (3.5 Hz) frequency and stated 72-hour power reserve reflect a search for balance: enough cadence for stability, enough autonomy for a multi-day watch rotation. The distinctive point is the constant-force barrel combined with an internal Geneva-style stop-work, which isolates the most consistent portion of the mainspring’s torque curve. In real use, the promise is more stable energy, hence more consistent timekeeping across the winding cycle.

This mechanics is not only a precision claim: it is also designed as readable engineering theatre, with components placed to be understood and a level of hand-finishing that is part of the manufacture’s DNA. Over the long term, servicing follows the logic of a high-end watch: proper service conditions, functional checks and water-resistance checks, and attention to shocks, especially because the open construction invites you to wear it as a genuine daily piece. The advantage of a coherent architecture is logical maintenance: everything is built to work together, not to stack effects.

Timeline markers and main models (2019–2025)

(2019) Armin Strom Gravity Equal Force System 78 launch :

This first milestone establishes the full vocabulary: a 41 mm steel case, open movement-side architecture, a visible micro-rotor, and above all the implementation of a constant-force barrel assisted by a Geneva-style stop-work to stabilize torque delivery. The off-centre dial preserves straightforward time reading despite the exposed organs, while the balance of brushed and polished finishes delivers a sport-chic result rather than a fragile object. The stated 72-hour power reserve and 3.5 Hz frequency place the watch in a very modern register, suited to rotation. It is also a watch that explains its technique: you can see energy being managed and understand why regularity sits at the center of the promise. The most representative launch reference is Armin Strom Gravity Equal Force ST19-GEF.90.AL.M.35.

(2021) Armin Strom Gravity Equal Force Ultimate Sapphire Grey sapphire dial :

With the Ultimate Sapphire, the brand pushes transparency further: the off-centre time dial becomes grey-tinted sapphire, reinforcing the “floating” dial impression and freeing even more of the view onto the components. This variant highlights architecture reading: sculptural bridges, a dense micro-rotor (often associated with tungsten), and the constant-force barrel become a landscape, while the time indication remains clear on the left. The case keeps the baseline proportions, with a stated height around 12.65 mm and a 3 ATM water-resistance level consistent with careful daily wear. It is a version that turns the Gravity Equal Force into a more optical piece, where light becomes part of the experience. The reference to cite is Armin Strom Gravity Equal Force Ultimate Sapphire ST21-GEF.SA.

(2024) Armin Strom Gravity Equal Force Ultimate Sapphire Purple Purple guilloché plate :

This edition adds a stronger color signature, centered on a purple guilloché mainplate attributed to traditional artisanal work, while keeping the open structure and off-centre sapphire dial. The wrist benefit is twofold: color adds emotional depth, and guilloché creates a texture that changes with angle, avoiding a flat feel on a watch that is already highly architectural. Technically, the logic remains that of an automatic micro-rotor calibre and constant-force barrel, with an integrated stop-work intended to stabilize energy delivery across the stated reserve. The whole remains wearable thanks to the 41 mm diameter, and it belongs to a limited production framework that reinforces perceived rarity. The corresponding reference is Armin Strom Gravity Equal Force Ultimate Sapphire ST24-GEF.SA.

(2024) Armin Strom Gravity Equal Force Ultimate Sapphire Blue “Glacial” blue plate :

The Blue version leans into a cooler, brighter palette, pairing a textured blue mainplate with a grey off-centre sapphire dial that highlights rhodium-toned components. The practical advantage of a lighter blue on this architecture is clearer reading: mechanics separate more distinctly, and the eye distinguishes planes between bridges, barrel, and gear train more easily. The stated characteristics remain consistent with the family: 41 mm steel case, roughly 12.65 mm height, 3 ATM water resistance, and the ASB19 calibre with 72 hours of power reserve and an integrated Geneva stop-work within the barrel. This execution strengthens the impression of a watch that is technical yet calm, readable even when you glance quickly. The associated reference is Armin Strom Gravity Equal Force Ultimate Sapphire ST24-GEF.BLU.

(2025) Armin Strom Gravity Equal Force Ultimate Sapphire Rose Gold 18K rose-gold case :

This 18K rose-gold variant changes the watch’s posture: the mechanical principle stays the same, but the case material brings a different warmth and density—dressier and more object-like. The composition combines brown and gold tones, with the off-centre sapphire dial preserving the floating effect, while the bridges take on a matching coloration. The movement architecture remains widely visible from both sides, and the constant-force concept stays central: internal Geneva-style stop-work, a barrel designed for more regular delivery, and a micro-rotor that winds efficiently without hiding the mechanical landscape. Annual production is stated as limited, reinforcing the sense of rarity while keeping everyday wearability. The reference to retain is Armin Strom Gravity Equal Force Ultimate Sapphire RG24-GEF.SA.

(2025) Armin Strom Gravity Equal Force Ultimate Sapphire Salmon Salmon PVD plate :

The Salmon version introduces a salmon tone on the mainplate via a PVD treatment, offering a warmer, more contemporary mood than grey or blue variations. On an open watch, color is not just cosmetic: it reshapes depth reading because it changes how the eye separates bridges, barrel, and gear train. This edition keeps the 41 mm steel case and the transparency spirit of the off-centre sapphire dial, while maintaining stated 3 ATM water resistance and a height around 12.65 mm. The mechanics remain founded on the ASB19 calibre, with a constant-force barrel and integrated stop-work intended to maintain stable energy delivery across the stated reserve. The corresponding reference is Armin Strom Gravity Equal Force Ultimate Sapphire ST24-GEF.SAL.

Finally, keep the complication logic in mind: the appeal here is not adding functions, but stabilizing energy. If you like a watch whose sophistication is felt through regularity and construction, the Gravity Equal Force is highly coherent. To choose between editions, compare wrist feel and daily readability, because that is where the real difference lives. Your best choice will be the one you want to wear often. Other customers’ opinions are essential.

Conclusion

The Gravity Equal Force is for those who want contemporary fine watchmaking that is readable and wearable, yet capable of showing a real engineering solution instead of merely talking about it. Its identity rests on an open architecture and a constant-force barrel paired with internal stop-work, with an off-centre dial that keeps the time immediately accessible. Choosing between variants depends mainly on your taste for color, your daily lighting, and whether you prefer steel or rose gold, more than on any change in mechanical philosophy. To refine your decision with concrete wearer feedback, consult Dialicious customer reviews.

(Updated March 2026)