Skip to content
The Encyclopedia of Horology

Wristwatch · Chronograph wristwatch

Omega Speedmaster Mark IV, Ref. ST 176.009

Partially verified

This Omega Speedmaster Mark IV, identified by reference ST 176.009 and movement number 34684219, is a self-winding stainless steel chronograph wristwatch produced during the late 1970s. The watch features a two-body, tonneau-shaped brushed steel case measuring 42 by 45 mm, with a thickness of 15.5 mm. It is equipped with hooded lugs and a screw-down case back embossed with the Seamaster logo. The watch is powered by the copper-colored Caliber 1045, which incorporates 17 jewels, a straight-line lever escapement, and a shock absorber. The dial is black with luminous baton indexes, displaying day and date apertures, subsidiary dials for seconds and a 12-hour register, and a 24-hour indicator. A central white hand acts as a 60-minute register. The tachometer scale is reverse-painted on the sapphire crystal, and the watch is completed with a stainless steel Omega bracelet featuring a deployant clasp.

Omega Speedmaster Mark IV in stainless steel with a black dial and tachometer scale on the crystal.
Omega Speedmaster Mark IV in stainless steel with a black dial and tachometer scale on the crystal. — Antiquorum. Rights pending — permission not yet requested. Original source

Catalogue identity

Source
catalog.antiquorum.swiss
Category
Wristwatch · Chronograph wristwatch
Maker / attribution
Omega
Reference
ST 176.009
Catalogue / lot identifier
20
Source-reported date
late 1970s
Source-reported place
Not established
Source-reported serial
34684219

Source-reported attribution and specifications are not independent authentication. A listing does not establish present ownership, current display, availability or permission to reproduce.

Object description

Case and Crystal

The watch is housed in a two-body, brushed stainless steel case characterized by a distinct tonneau shape and hooded lugs. It measures 42 mm by 45 mm with a depth of 15.5 mm.

The crystal construction is integral to the dial presentation, featuring a tachometer scale graduated to 500UPH that is reverse-painted directly onto the sapphire. This configuration creates a deep appearance for the scale, protecting the markings from exterior abrasion while maintaining the clean lines of the bezel.

Evidence for this section
  • “Two-body, brushed, screw-down case back with the embossed Seamaster logo, hooded lugs”
  • “tachometer scale graduated to 500UPH reverse-painted on the sapphire crystal”

Dial and Functions

The black dial is set with luminous baton indexes and white baton hands. It provides significant information through its multi-register layout, including subsidiary dials for seconds and a 12-hour register. The day and date are shown through apertures located on the right side of the dial.

Additional functional displays include a 24-hour indicator facilitated by an arrow on a revolving disc, allowing for night and day identification. The 60-minute chronograph register is integrated into the central dial by means of a distinctive white jet hand, separate from the primary time-telling functions.

Evidence for this section
  • “Black with luminous baton indexes”
  • “subsidiary dials for the seconds and the 12-hour register, the 24 hours with night/day indication by means of an arrow on a revolving disc”
  • “60-minute register by means of a central white jet hand, apertures for the day and date.”

Movement and Condition

The timepiece is powered by the Omega Caliber 1045 movement, a copper-colored caliber featuring 17 jewels. It utilizes a straight-line lever escapement, a monometallic balance, and a self-compensating flat balance spring, designed to provide consistent self-winding performance.

Regarding the condition of the watch, the auction house grades the dial as 'As new' and the case as 'Very good'.

Evidence for this section
  • “Cal. 1045, copper-colored, 17 jewels, straight line lever escapement”
  • “Overhaul recommended, at buyer's expense”
  • “Grading System Grade: AA Very good”

Open research questions

  • What is the specific production timeframe within the late 1970s for this movement number?
  • Is the stainless steel bracelet original to this specific watch reference?

Source evidence

Recorded claims and source quotations for Omega Speedmaster Mark IV, Ref. ST 176.009
FieldSource-reported valueSource quotation
MakerOmega“Omega Speedmaster, Automatic”
ReferenceST 176.009“Ref. ST 176.009”
Movement Number34684219“movement number 34684219”
Case Dimensions42 mm x 45 mm“DIM. 42 x 45 mm.”
Movement CaliberCal. 1045“Cal. 1045”
Case BackScrew-down with embossed Seamaster logo“screw-down case back with the embossed Seamaster logo”
TachometerScale to 500UPH on crystal“tachometer scale graduated to 500UPH reverse-painted on the sapphire crystal”
Jewel Count17“17 jewels”

Visible details

  • Tachometer scale reverse-painted on the sapphire crystal
  • Hooded lug design
  • 24-hour day/night revolving disc indicator
  • Black dial with luminous baton indexes

Research qualifications

  • Auction description advises that an overhaul is recommended
  • Movement condition graded as 2*

Photograph identity and source facts were screened before import; rights clearance remains pending.

Consulted source

OMEGA SPEEDMASTER MARK IV STEEL Omega Speedmaster, Automatic, movement number 34684219, Ref. ST 176.009. Made in the late 1970s. Fine and rare, self-winding, water-resistant, tonneaushaped, stainless steel wristwatch with day, date, round button chronograph, 12-hour register, central minute recorder, tachometer, the 24 hours with night/day indication, and a stainless steel Omega bracelet with deployant clasp.

Reviewed 2026-10-26 · Record ca81ed6aa1

Terms in this record

Glossary explanations for terms named in this object’s record.

Other chronograph wristwatch records