Omega Speedmaster Speedmaster Professional Moonwatch 3861 Sedna Gold - Diamond / Brown / Bracelet

Reference 310.55.42.50.13.001

About this watch

The Omega Speedmaster Professional Moonwatch 3861 Sedna Gold - Diamond / Brown / Bracelet is a masterpiece of horology, blending art, history, and cutting-edge technology. Crafted from Sedna Gold, this watch boasts a unique color that's both warm and striking. Its round shape and sunburst brown finish give it a luxurious feel, while the diamond-set bezel adds a touch of elegance. The 3861 is equipped with a chronograph feature, allowing you to measure elapsed time with precision. At its heart lies the Omega caliber 3861, an updated version of the legendary caliber 861/1861, featuring a co-axial escapement and silicon balance spring for accuracy and reliability. Master Chronometer certified by METAS, this watch has undergone rigorous testing to withstand magnetic fields of up to 15,000 gauss. Its sleek design and exceptional craftsmanship make it a standout in any collection. Whether you're at a formal event or a casual outing, this watch is sure to turn heads.

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Key Features

Sedna Gold case
Manual-winding chronograph movement
Co-axial escapement and silicon balance spring
Master Chronometer certified by METAS
Diamond-set bezel
Water resistance up to 50 meters
42.00 mm diameter and 13.18 mm height

Specifications

Brand

Omega

Family

Speedmaster

Model

Speedmaster Professional Moonwatch 3861 Sedna Gold - Diamond / Brown / Bracelet

Reference

310.55.42.50.13.001

Movement

3861

Movement Features

Small Seconds, Hours, Minutes
Chronograph
Chronometer

Case

Sedna Gold 42mm

Dial Color

Brown

Crystal

Sapphire

Water Resistance

Current Listings

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

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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

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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

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

Omega - 329.30.44.51.01.001 · $5,750

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

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Omega Speedmaster Professional Moonwatch Hesalite Ref. 310.30.42.50.01.001 2022

Omega - 310.30.42.50.01.001 · $5,550

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

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