Omega Speedmaster Triple Calendar 3520.50 MK40

Model: Omega Speedmaster Triple Calendar Ref. 3520.50 “Mk40”

Overview:
The Omega Speedmaster Triple Calendar Ref. 3520.50, commonly known as the “Mk40,” is one of the more complicated executions of the neo-vintage Speedmaster. Produced during the 1990s, the Mk40 combines a full chronograph with day, date, month and 24-hour indications, fitting an impressive amount of functionality into a compact approximately 39mm case.

Despite the number of complications, the dial remains surprisingly balanced and becomes remarkably intuitive once familiar with its layout.

History:
The Mk40 belongs to an interesting period of Speedmaster production during the 1990s, when Omega experimented with complications and configurations beyond the traditional hand-wound Moonwatch. Rather than the familiar three-register chronograph alone, the Ref. 3520.50 incorporated a complete triple-calendar display alongside its automatic chronograph functionality.

The model was produced for a relatively short period and has subsequently become one of the more recognizable neo-vintage Speedmaster variants. As interest in 1990s Omega and more compact Speedmaster references has increased, the Mk40 has developed a strong following among collectors looking beyond the traditional Professional models.

Specifications and Condition:

Overall: Great Condition
Case: Great Condition
Crystal: Clean
Dial: Clean
Movement: Excellent
Bracelet/Strap: Original Omega Stainless Steel Bracelet
Includes: Watch

Movement:

Omega Caliber 1151 Automatic
Based on the Valjoux 7751

Dimensions:

Approximately 39mm Case Diameter
Approximately 44mm Lug-to-Lug
18mm Lug Width

Design Details:

Black Multi-Function Dial
Central Airplane-Tipped Pointer Date Hand
Day & Month Apertures at 12 o’clock
Running Seconds & 24-Hour Day/Night Indicator at 9 o’clock
30-Minute Chronograph Counter at 12 o’clock
12-Hour Chronograph Counter at 6 o’clock
Central Chronograph Seconds

Closing Note:
The Speedmaster Mk40 is a fascinating departure from the traditional Speedmaster formula. Its Caliber 1151 manages to combine an automatic chronograph, triple calendar, central pointer date and 24-hour indication within a compact case that remains highly wearable by modern standards.

The distinctive airplane-tipped date hand and densely functional yet balanced dial give the Ref. 3520.50 an identity entirely its own within the Speedmaster family. With growing appreciation for neo-vintage Omega and increasingly strong interest in smaller, more complicated references from the 1990s, the Mk40 stands as one of the more interesting and characterful Speedmasters of its era.