Octanis Sigma GMT 42 - Founders Edition - Astronomical Twilight

The Edge of the Void: Modern Navigation Meets Horological Precision.

Named after the south polar star, the Sigma GMT is purpose-built for those who chart their own course across land, sea, and sky.

Astronomical Twilight: Navigating the Dark

In the final phase of twilight before total nocturnal pitch, the sun dips 18 degrees below the horizon. The atmosphere glows in a deep, electric blue while the vastness of space reveals its first celestial beacons.

The Astronomical Twilight edition captures this exact transition: a crisp white dial bounded by a deep blue internal 24-hour rehaut. It’s high-contrast, ultra-legible, and framed in architectural 316L stainless steel.  An homage to early maritime octants used by voyagers who trusted only the stars to guide them home.

True Flyer GMT Power: The Miyota 9075

When crossing time zones, true navigators don't stop their engines. Powered by the Japanese Miyota 9075 automatic caliber, the Sigma is a genuine Flyer GMT.

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

• High-Beat Smoothness: 28,800 vph (4Hz) sweep for effortless precision.

• Exhibition Sapphire Caseback: Sapphire crystal on both front and back reveals the decorated rotor and mechanical beating heart underneath.

Dual-Crown Internal Rehaut: 3 Time Zones on Command

External bezel inserts chip, fade, and snag. The Sigma features an internal rotating 24-hour rehaut operating via a secondary knurled crown at the 2H position.

Protected under flat sapphire crystal with anti-reflective coating, this internal bezel allows you to track a third time zone on demand while keeping the case sleek, protected, and rated for 100 meters (10 ATM) of water resistance.

Hand-Inspected & Hand-Regulated

Before GPS, navigators relied on the octant: an instrument that demanded absolute precision because lives depended on it. We build Octanis in that exact spirit. Every piece in this 120-unit Founder’s Edition run is personally inspected and hand-regulated before leaving our workbench.

What’s Included in Your Voyage Package:

• 3-Watch Travel Roll: Premium canvas and leather storage for life on the move.

• Bonus FKM Rubber Strap: Color-matched in deep astronomical blue for water and sports wear.

• Quick-Adjust Bracelet: On-the-fly micro-adjustment buckle for instant sizing shifts as your wrist changes throughout the day.

• Commemorative Warranty Card & Octanis Seal.

Technical Specifications

Instruction Manual Download

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