Octanis Sigma GMT 42 - Founders Edition - Nautical Twilight

Where Sea Meets Sky: The True Voyager’s Tool.

Named after the south polar star, the Sigma GMT is built for navigators who read the horizon and master the stars.

Nautical Twilight: The Navigator’s Horizon

In the quiet expanse between dusk and nightfall, when the sun sits between 6 and 12 degrees below the horizon, sailors witness Nautical Twilight. It is the exact celestial window where the horizon remains visible to the eye while the brightest navigational stars reveal themselves overhead.  The precise moment mariners took up the octant to chart their position across the open ocean.

The Nautical Twilight edition honors this historic voyage with a deep maritime blue dial offset by a striking, high-visibility orange internal 24-hour rehaut. Designed for high contrast at sea or in flight, it frames modern horology in classic tool-watch utility.

True Flyer GMT Power: The Miyota 9075

When crossing ocean spans or flying across continents, true navigators need seamless timekeeping. Powered by the Japanese Miyota 9075 automatic caliber, the Sigma is a genuine Flyer GMT.

Unlike entry-level "office" GMTs, pulling the crown lets you jump the local hour hand in precise one-hour increments without stopping the balance wheel or disrupting your home time.

• High-Beat Precision: 28,800 vph (4Hz) sweep for smooth, reliable timekeeping.

• Dual Sapphire Construction: Flat sapphire crystal with anti-reflective coating up front, paired with an exhibition sapphire back to admire the mechanical movement beneath.

Dual-Crown Internal Rehaut: 3 Time Zones on Command

External bezel inserts chip, scratch, and snag. The Sigma houses an internal rotating 24-hour rehaut operated via an independent knurled crown at the 2H position.

Safely sealed beneath flat sapphire crystal and rated for 100 meters (10 ATM) of water resistance, this secondary clock display allows you to track a third time zone instantaneously with a turn of the wrist.

Hand-Inspected & Hand-Regulated

Before GPS, ocean passage depended on the octant: an instrument built with zero tolerance for error because lives depended on it. Every piece in this 120-unit Founder’s Edition run is personally inspected and hand-regulated on our workbench before shipping.

What’s Included in Your Voyage Package:

• 3-Watch Travel Roll: Heavy-duty canvas and leather travel storage.

• Bonus FKM Rubber Strap: Color-matched in vibrant orange for high-performance sea and sport wear.

• Quick-Adjust Stainless Bracelet: Micro-adjustment buckle for rapid sizing shifts as your wrist changes temperature.

• Commemorative Warranty Card & Octanis Seal.

Technical Specifications

Instruction Manual Download

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