[Press Release] For Only Watch 2011, Swiss luxury watch brand Maurice Lacroix unveils a unique piece based on the Masterpiece Roue Carrée Seconde, the model featuring an innovative square-wheel mechanism. Originally introduced in 2010, Masterpiece Roue Carrée Seconde equips the first square-wheel mechanism in the history of watchmaking.

This mechanism was developed by the watchmaker and engineer Michel Vermot, head of the development department at Maurice Lacroix. He worked in association with the Swiss Higher Education Institution, the Haute Ecole Arc, in Le Locle. Since, by definition, the gear profile of non-circular wheels cannot be regular, the shape of the teeth presented the greatest challenge in guaranteeing a constant transmission of power. The wheels were produced using silicon-machining technology to make very high-precision, lightweight and self-lubricating micro-components that cannot be manufactured with such quality using traditional production methods.

The movement in the Masterpiece Roue Carrée Seconde draws the eye inexorably into its spell. The regular movement of the square wheel, with its captivating geometric openwork shape, makes the small seconds hand come to life before the observer’s very eyes. The square and cloverleaf-shaped wheels were specially made for this watch out of silicon, and decorated with a unique and inimitable pattern, with plays of color that change constantly with viewing angle, illumination or movement of the square and clover-leaf wheels (Sigatec SA®, Kamic SA®). But that is not the only exclusive and distinctive feature of this one-of-a-kind timepiece. In a detail included specially for collectors who take delight in the unusual, the Only Watch logo is featured on the square wheel – a little surprise that is visible only with the aid of a magnifying glass.

The square wheel is driven by a toothed, cloverleaf-shaped wheel. Both wheels engage with the same precision as traditional round wheels. The constant, regular movement creates a wonderful visual spectacle.

To make the seconds hand more decidedly prominent, the hours and minutes are indicated by a centrally mounted hand. The power reserve indicator at 3 o’clock is the perfect completion to this well balanced arrangement. The hours, minutes and power reserve are featured directly on the main plate, which serves as the dial. A black, sand-blasted finish completes the embellishment. The case back has a large sapphire crystal offering a view of the elegant ML 156 mechanical movement, which is decorated with a Grand Colimaçon design in the finest Swiss watchmaking tradition.

The Masterpiece Roue Carrée Seconde for the Only Watch 2011 auction represents a breath-taking combination of technology and craftsmanship. It is an exciting blend of technology and aesthetics, lending a new face to time. It is uncompromisingly masculine and intentionally technological. Ready, too, to give real innovative impetus to the fight against muscular dystrophy.

Technical Specifications

Case:
- Steel, Φ 43 mm, sand-blasted finish
- Domed sapphire crystal with anti-reflective coating on both sides
- Screwed case back with wide sapphire crystal
- Water-resistant to 50 m / 5 atm

Movement Bridge / dial:
- The dial has been created on the main plate of the movement itself and is decorated with a black sand-blasted finishing with raised polished indexes (hours, minutes and power reserve); obtained with a special chemical and laser surface treatment by DM Surface SA®).
- The square wheel and clover-leaf mesh to transfer power with the same precision as the cogs in their circular counterparts; in addition the wheel is used to indicate the seconds
- The square wheel and clover-leaf wheel are highlighted by a circular opening on the movement’s main plate itself, decorated with a fine sand-blasted background.

Hands:
- Trailing square wheel and clover-leaf wheel in silicon for the seconds display, designed with a unique pattern, created especially for this watch by Karmic SA® and made by Sigatec SA®.
- But not only the design pattern is unique and inimitable: The Only Watch logo is available but visible only with a magnifying glass or very good eyes
- No visible rotation axis
- PVD-coated black gold, diamond-polished hours, minutes and power reserve hands

Strap / bracelet:
- Mat black large-scale crocodile-skin strap, lined with black calfskin and black over-stitching

Buckle:
- Folding steel clasp with push-buttons
- Sand-blasted finish

Movement:
- ML 156 manually wound mechanical movement
- Developed in association with the HE-ARC, manufactured and assembled by Maurice Lacroix
- Patented design (square wheel / cloverleaf-shaped wheel)

Functions:
- Hours and minutes indicated by centrally mounted hands
- Small seconds indicated on square wheel at 6 o’clock
- Power reserve indicator at 3 o’clock

Frequency: 18,000 vibrations per hour, 2.5 Hz
Power Reserve: 45 hours
Jewels: 34
Settings: five positions after watch is fully wound and after 24 hours
Embellishments: Grand Colimaçon, rhodium