Omega Speedmaster Speedmaster Professional Moonwatch 3861 Stainless Steel / Black / Plexi / Kanjar Oman

Reference 310.30.42.50.01.003

About this watch

The Omega Speedmaster Professional Moonwatch 3861 is a piece of history wrapped around your wrist, with its rich lineage and modern upgrades capturing the hearts of watch enthusiasts and collectors alike. This manual-winding chronograph movement features a co-axial escapement and silicon balance spring, making it resistant to magnetic fields up to 15,000 gauss. The plexi glass provides a warm, vintage feel that many collectors adore, while the stainless steel case measures 42mm in diameter and has a water resistance of 50 meters. This timepiece is perfect for everyday wear, suitable for both formal and casual occasions. With its stunning design, robust movement, and versatility, it's a celebration of heritage, precision, and style.
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Key Features

  • Omega Caliber 3861 Movement
  • Plexi Glass with Vintage Feel
  • 42mm Stainless Steel Case
  • 50m Water Resistance
  • Manual-Winding Chronograph Function
  • Co-Axial Escapement and Silicon Balance Spring

Specifications

Brand
Omega
Family
Speedmaster
Model
Speedmaster Professional Moonwatch 3861 Stainless Steel / Black / Plexi / Kanjar Oman
Reference
310.30.42.50.01.003
Movement
3861
Movement Features
  • Small Seconds, Hours, Minutes
  • Chronograph
  • Chronometer
Case
Stainless Steel 42mm
Dial Color
Black
Crystal
Plexi
Water Resistance
50

Current Listings

[WTS] Incredible Vintage 18K Good Omega Speedmaster “Tribute To Astronauts” Ref BA145.022 Unpolished Collector Example!

Incredible Vintage 18K Good Omega Speedmaster “Tribute To Astronauts” Ref BA145.022 Unpolished Collector Example!

Omega - BA145.022 · $47,500
This is a rare and historic Omega Speedmaster 'Tribute to Astronauts' ref BA145.022-69, one of only 1014 made in 1969. It features an 18K gold dial, correct maroon bezel, and solid 18K yellow gold case with patina.

  • Condition: Excellent, unpolished with patina
  • Case size: 42MM
  • Diameter: 42MM case diameter
  • Bracelet length: 7.5 inches
Posted at
Apr 26, 2026, 10:23 PM
Active
[WTS] Omega Speedmaster Reduced 3510.21 Limited Edition (2,000 Pcs) Marui 39mm , B&P  - $5,550

Omega Speedmaster Reduced 3510.21 Limited Edition (2,000 Pcs) Marui 39mm , B&P - $5,550

Omega - 3510.21 · $5,550
Up for sale is my Omega Speedmaster 3510.21 in great shape, measuring 39mm with an automatic movement.

  • Condition: Very good condition
  • Movement: automatic
  • Case size: 39mm diameter
  • Bracelet type: original Omega Steel bracelet
Posted at
Apr 26, 2026, 10:05 PM
Active
[WTS] Omega / Speedmaster date / Silver Dial / 40mm / Full Set

Omega / Speedmaster date / Silver Dial / 40mm / Full Set

Omega - 3211.30 · $3,500
This Omega Speedmaster features a silver dial, 40mm case size, and is part of the full set.

  • Condition: Excellent Condition
  • Water Resistance: unknown
  • Buckle Size: Fits 7.5"
  • Shipping Included: true
Posted at
Apr 26, 2026, 10:02 PM
Active
[WTS] Omega Speedmaster Racing - 329.30.44.51.01.001 - Box and Papers - Price Reduced

Omega Speedmaster Racing - 329.30.44.51.01.001 - Box and Papers - Price Reduced

This Omega Speedmaster Racing Chronograph is a pre-owned model with a 44.25mm case size, featuring a chronograph function and minor wear throughout.

  • Condition: pre-owned with minor wear
  • Size: 44.25mm diameter
  • Bracelet material: stainless steel
Posted at
Apr 26, 2026, 8:39 PM
Active
[WTS] Omega Speedmaster Professional Moonwatch Hesalite Ref. 310.30.42.50.01.001 2022

Omega Speedmaster Professional Moonwatch Hesalite Ref. 310.30.42.50.01.001 2022

A modern Omega Speedmaster Professional Moonwatch Hesalite with a classic vintage-inspired look and updated Co-Axial Master Chronometer movement, in the reference number 310.30.42.50.01.001.

  • Condition: good pre-owned condition
  • Movement type: Co-Axial Master Chronometer
Posted at
Apr 26, 2026, 7:32 PM
Active
[WTS] Omega Speedmaster Professional Moonwatch Ref. 310.30.42.50.01.001

Omega Speedmaster Professional Moonwatch Ref. 310.30.42.50.01.001

  • Watch type: Speedmaster Professional Moonwatch
Posted at
Apr 26, 2026, 6:56 PM
Active
[WTS] Omega Speedmaster Racing Chronograph 44.25mm – BOX & PAPERS – 329.30.44.51.04.001 Active Warranty & Dec 2025 Service Records

Omega Speedmaster Racing Chronograph 44.25mm – BOX & PAPERS – 329.30.44.51.04.001 Active Warranty & Dec 2025 Service Records

This Omega Speedmaster Racing Chronograph is a 44.25mm timepiece with additional details available upon request.

  • Case Size: 44.25mm diameter
  • Warranty: Active Warranty
Posted at
Apr 26, 2026, 5:22 PM
Active
[WTS] 2024 Omega Speedmaster Moonwatch – Full Set – $4850 Shipped

2024 Omega Speedmaster Moonwatch – Full Set – $4850 Shipped

This is a 2024 Omega Speedmaster Moonwatch, an iconic timepiece in its latest Hesalite configuration.

  • Condition: Excellent with minor hairline scratches on the clasp
  • Case size: 42mm
  • Crystal type: Hesalite
  • Movement type: Manual-wind Co-Axial Master Chronometer
Posted at
Apr 26, 2026, 1:05 PM
Active
[WTS] OEM Omega Speedmaster Rubber Strap & Deployant Small Size

OEM Omega Speedmaster Rubber Strap & Deployant Small Size

· $490
Additional Details: This is a well-maintained OEM Rubber and Deployant with minimal scratches on the deployant.

  • Condition: well-maintained
  • Lug width: 20mm
  • Shipping method: USPS priority
  • Shipping area: USA only
Posted at
Apr 26, 2026, 12:51 PM
Active