Omega Seamaster “Big Blue” 176.004 (1970–1972) Watch

 

Omega Seamaster “Big Blue”

Reference: 176.004
Production: ~1970–1972
Nickname: Big Blue
Category: Professional dive chronograph

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Core Specs

• Case: Stainless steel monobloc (front-loading)

• Diameter: ~46 mm

• Thickness: ~15.5 mm

• Water resistance: 120 m (original rating)

• Crystal: Mineral (originally)

• Movement: Omega Caliber 1040

  • Automatic chronograph

  • Column wheel

  • 22 jewels

  • 28,800 bph

• Functions:

  • Chronograph (12-hour totalizer)

  • Central chronograph minutes

  • Date at 3

  • Running seconds at 9

This was Omega’s first automatic chronograph movement, developed with Lemania (the same brain trust behind Speedmasters).

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Why It’s Called “Big Blue”

• Massive 46 mm case — absolutely enormous for the early ’70s

• Striking blue dial and blue anodized aluminum bezel

• Bold white hands and orange chronograph accents

• One of the loudest, most unapologetic dive chronographs ever made

It wears huge, but in a very intentional, tool-watch way.

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Design & Dial Details (Collector Checklist)

Dial

• Deep matte navy blue

• White applied hour markers

• Bright orange central chronograph minute hand

• “Seamaster” script above 6

• Sub-dial layout:

  • 9 o’clock: running seconds

  • 3 o’clock: 24-hour indicator

  • 6 o’clock: 12-hour chronograph

Bezel

• Blue anodized aluminum

• Integrated into the case (not removable like modern bezels)

• Original bezels fade beautifully—uniform fading is preferred

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Case & Bracelet

• Monocoque case → movement accessed from the front

• Sharp original brushing is crucial for value

• Common original bracelets:

  • Omega 1162 / 172

  • Omega 1159 / 154

• Many were sold on rubber; original Omega rubber straps are unicorn-rare

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Common Issues to Watch For

• Over-polished cases (kills that crisp ’70s geometry)

• Faded or chipped bezel inserts (some fading is good—damage isn’t)

• Incorrect hands (orange chrono hand is often replaced)

• Moisture damage (120 m rating ≠ modern dive standards)

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Collector Verdict

The Big Blue is:

• One of Omega’s boldest designs ever

• Historically crucial (first auto chrono)

• Still slightly underpriced relative to its importance

It’s not a daily wear watch—it’s a statement piece. You don’t slip it under a cuff. You announce it.