1975 Omega Automatic Calendar Watch 166.0117 Cal. 1020 17 Jewels 35mm Wristwatch

Watch Overview

Offered here today is an excellent timepiece: A vintage Omega Automatic Calendar wristwatch, reference 166.0117 and dated from 1975 based on the serial number.

It is a self-winding watch, powered by an automatic movement caliber Omega 1020 with 17 jewels, sweep-second hand, and day/date indicator. This Swiss-made timepiece offers a 42-hour power reserve and beats at a high frequency of 28,800 vibrations per hour.

Still has the original sunburst champagne dial featuring gold-tone baton hour markers, luminous dots, luminous matching gold-tone hands and the day/date indicator is at 3 o'clock.

Cased in a 35mm round gold plate bezel and stainless steel case back with classic lugs design. It comes on a black leather strap. Fully inspected and authenticated, it remains in very good vintage condition consistent with age and use. It is ready to wear and enjoy.

Product Details

General Specifications

• Brand: Omega
• Type: Wristwatch
• Reference: 166.0117
• Model: Automatic Calendar
• Year / Era: 1975 - Vintage
• Gender: Men's
• Country of Manufacture: Switzerland

Dial & Display

• Display: Analog
• Color: Champagne
• Features: Baton hour markers. Sweep-second. Day/date indicator

Movement

• Type: Self-winding
• Caliber: Omega 1020
• Jewels: 17
• Movement Functions:
  • Sweep seconds
  • Day-date indicator
• Power Reserve: 42 hours
• Frequency: 28,800 vph

Case & Band

• Material: Gold plate and Stainless steel
• Case Shape: Round
• Bezel: Fixed. Smooth
• Crystal: Acrylic
• Back: Screw
• Crown: Push-pull
• Band Type: Black leather two-piece strap
• Case Back Markings: Plaque OR G20 Microns Omega Watch Co. - Fab. Suisse Swiss Made - Acier Inoxidable - 166.0117
• Case Back Engraving: Jack Westhead for 25 Years Service 1952-1977 Eli Lily and Company

Case Measurements (mm)

• Case Size: 35
• Case Diameter w/Crown: 37.6
• Case Lug to Lug: 41.8
• Case Thickness: 11
• Lug Width: 18
• Band Width: 18

Additional Info

• Box & Papers: NO
• Condition: The watch is in good condition, some signs of wear consistent with use and aged, a solid case, bezel and dial.
• Extras: This timepiece has been fully inspected and authenticated by our in-house watchmaker, confirming that it runs accurately. It is ready to wear.

History & Legacy of Omega

Omega is a Swiss luxury watchmaker known for producing high-quality and prestigious timepieces. The company was founded in 1848 by Louis Brandt in La Chaux-de-Fonds, Switzerland; Louis Brandt started as a watchmaker, and he produced key-wound pocket watches. Originally, it was called "Louis Brandt et Frère" and they primarily produced pocket watches and it was until 1903 that the company officially adopted the name "Omega."

Throughout its history, Omega has continued to innovate and produce high-quality timepieces. Today, it remains one of the most prestigious and respected Swiss watchmakers, offering a diverse range of collections that cater to various lifestyles and tastes. Today, Omega continues to be a prominent and highly regarded Swiss luxury watch brand.

Omega Constellation: The Omega Constellation was introduced in 1952 as a chronometer-certified collection, following the success of the 1948 Centenary, Omega’s first automatic chronometer. Known for its precision, the Constellation featured automatic movements and the signature observatory medallion caseback. In 1970, Omega launched the Constellation Electroquartz, embracing the quartz revolution. Today, the Constellation remains a symbol of Omega’s commitment to accuracy, innovation, and timeless design.

About Second Hand Horology

At SECOND HAND HOROLOGY, we offer a curated selection of watches ranging from vintage to modern, including both brand-new and pre-owned timepieces. We’re committed to quality, accuracy, and integrity. Our listings feature:

Professional, unedited photography and clear, transparent descriptions. Every watch is thoroughly inspected and securely packaged to ensure a confident, seamless buying experience.

We also warmly invite you to visit our physical shop and explore the collection in person.

Contact Us

We appreciate you checking out our listing! Don’t hesitate to reach out with questions, offers, or just to talk watches — we love what we do and enjoy connecting with fellow enthusiasts.

Thank you for your business—we truly appreciate your support and look forward to serving you again in the future!

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