Unworn, Omega Constellation Observatory, Ref# 140.93.39.21.99.001, box and papers.

The OMEGA Constellation Observatory Co-Axial Master Chronometer Ref. 140.93.39.21.99.001 is an extraordinary expression of haute horlogerie, created to celebrate OMEGA's unrivaled legacy in precision timekeeping. Crafted from exclusive Platinum-Gold, the 39.4 mm case is paired with a black alligator leather strap and showcases a design inspired by the historic Geneva Observatory. The striking yellow dial is complemented by diamond-polished dauphine hands and distinctive kite-shaped indexes in 18K white gold with a 950 Platinum-Gold PVD coating, offering exceptional elegance and legibility. Through the sapphire crystal caseback, the exceptional OMEGA Co-Axial Master Chronometer Calibre 8915 is fully visible, featuring a luxurious 18K Sedna™ Gold skeletonized rotor adorned with an applied 18K white gold Constellation Observatory medallion, enhanced by dark blue aventurine glass and white opal enamel detailing. As the world's first two-hand movement to achieve METAS Master Chronometer certification, the calibre delivers remarkable precision, resistance to magnetic fields up to 15,000 gauss, and a convenient time-zone function without interrupting the movement. A domed, bevelled sapphire crystal with anti-reflective treatment on both sides ensures optimal clarity, while the watch offers a 60-hour power reserve and water resistance to 30 meters.

TECHNICAL DATA

Movement

• OMEGA Co-Axial Master Chronometer Calibre 8915
• Self-winding mechanical movement
• METAS-certified Master Chronometer
• Co-Axial escapement with free-sprung balance and silicon balance spring
• Twin barrels mounted in series
• Anti-magnetic to 15,000 gauss
• Time-zone function
• 18K Sedna™ Gold rotor and balance bridge
• 60-hour power reserve
• Frequency: 25,200 vph (3.5 Hz)
• Functions: Hours, minutes

Case

• 39.4 mm Platinum-Gold case
• Yellow dial
• Diamond-polished 18K white gold dauphine hands with 950 Platinum-Gold PVD coating
• Diamond-polished kite-shaped 18K white gold indexes
• Domed, bevelled scratch-resistant sapphire crystal with anti-reflective treatment on both sides
• Transparent sapphire crystal caseback
• Water resistance: 30 m / 100 ft (3 ATM)
• Presented in a special marquetry box with the Constellation Observatory emblem

Dimensions

• Case diameter: 39.4 mm
• Thickness: 12.32 mm
• Lug-to-lug: 47.20 mm
• Between lugs: 19 mm
• Approximate weight: 121 g

Strap

• Black alligator leather strap
• Platinum-Gold pin buckle

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