Omega Speedmaster Speedmaster Professional Moonwatch Sapphire Sandwich / Strap
Reference 3873.50.31
About this watch
The Omega Speedmaster Professional Moonwatch Sapphire Sandwich, also known as the 3873.50.31, is a testament to the brand's rich history and commitment to precision. This luxury watch features a stunning black dial with contrasting white stick and dot indexes, giving it a classic yet modern vibe suitable for both formal and casual occasions. The round stainless-steel case strikes a perfect balance between presence and elegance, measuring 42mm in diameter. A sapphire crystal on both the front and back of the watch enhances durability and provides a stunning view of the intricate movement through the open case back. With its iconic design, reliable Omega caliber 1863 movement, and versatile wearability, this watch earns its place in any collection. Whether you're a history buff, a watch connoisseur, or someone looking to elevate your style, the Speedmaster is a worthy companion. It's not just about telling time; it's about cherishing every moment.
Key Features
- Omega caliber 1863 movement
- 48-hour power reserve
- 21,600 vibrations per hour
- Chronograph function for timing events
- Sapphire crystal on front and back of the watch
- Water resistance up to 50 meters
- Leather strap with secure buckle
Specifications
- Brand
- Omega
- Family
- Speedmaster
- Model
- Speedmaster Professional Moonwatch Sapphire Sandwich / Strap
- Reference
- 3873.50.31
- Movement
- 1863
- Movement Features
-
- Hours, Minutes, Small Seconds
- Chronograph
- Case
- Stainless Steel 42mm
- Dial Color
- Black
- Crystal
- Sapphire
- Water Resistance
- 50
Current Listings
![[WTS] Two Tone Omega Speedmaster Reduced](https://external-preview.redd.it/w8-wkeNiEyq60tpiHd01NbUeHiv47S--7J_gXy0Zgt4.jpeg?auto=webp&s=0fd98a91dd5016c3da476eea514c628806bc4b0b)
Two Tone Omega Speedmaster Reduced
A two-tone Omega Speedmaster Reduced in overall good condition with a white dial, gold subdials, and an 18k gold bezel.
- Condition: Good condition with wear on the case and bezel
- Movement: Cal 1140
- Case size: 39mm diameter

Omega SPEEDMASTER PROFESSIONAL MOONWATCH 3861 WHITE DIAL 2025 WARRANTY FULL SET
This is a new 2025 model Omega Speedmaster Professional Moonwatch with a 42mm stainless steel case and white dial, featuring a manual-winding chronograph movement with co-axial escapement.
- Condition: Excellent Condition
- Movement: 3861 Manual-Winding Chronograph
- Case material: Stainless Steel
- Diameter: 42mm
![[WTS] Omega Speedmaster Automatic MK40 Day Date Ref 3520.53](https://external-preview.redd.it/7nGkjbMhVxrm84CqOK5ux_m_3x-lP765HQ1Dz5Kr_aU.jpeg?auto=webp&s=914f577263d19c6a84251a5d3b5824ad90e22b02)
Omega Speedmaster Automatic MK40 Day Date Ref 3520.53
One of the coolest Speedmaster variants, featured in A Man and His Watch, with a tritium dial and luminova hands.
- Condition: Pre-owned, with wear and dings on the bezel, insert, and case
- Case size: 39mm diameter

Omega Speedmaster Professional Tokyo 2020 522.30.42.30.03.001
This Omega Speedmaster Professional Tokyo 2020 is a high-end watch that comes with its original boxes and books, but no warranty card. It's in excellent condition.
- Condition: Excellent condition
- Box And Papers: includes
- Warranty Card: no
![[WTS] Omega Speedmaster Professional Sapphire 3861](https://external-preview.redd.it/GFyeMHjiQugc7k3v7DpjwLCL0zKQBy4P6cRRNI8ynoc.jpeg?auto=webp&s=ba20feb41ea99b61fea9993fbc3097cd9d62b82c)
Omega Speedmaster Professional Sapphire 3861
A Omega Speedmaster Professional Sapphire Sandwich sold on an OEM rubber strap, also including an unworn leather strap and full kit of original accessories.
- Condition: Excellent preowned
- Strap included: 2
- Case condition: preowned

Omega Speedmaster - First Omega in Space - FOIS - 310.30.40.50.06.001 ( new )
This Omega Speedmaster 3861 Anniversary Series is a brand new First Omega in Space (FOIS) model, reference # 310.30.40.50.06.001, featuring a stainless steel case and Omega 3861 calibre.
- Condition: Brand New / Complete Set
- Case Size: 39.7mm
- Material: Stainless Steel
- Calibre: Omega 3861
![[WTS] White Omega Speedmaster Pro](https://preview.redd.it/8vigxlnkkc6f1.jpg?width=640&crop=smart&auto=webp&s=50e9a6ec643c18bfa7d032ecdc85d3cb870fd824)
White Omega Speedmaster Pro
A white dial Omega Speedmaster Pro comes with a box and card, and has a warranty dated July 2024.
- Box: yes, included
- Card: yes, included
- Warranty: until July 2026
![[WTS] OMEGA Speedmaster Dark Side of the Moon “Black Black”- DSOTM - 311.92.44.51.01.005](https://preview.redd.it/jpel7nirib6f1.jpg?width=640&crop=smart&auto=webp&s=d2afe3ae6f1cc6e1d4ac2e36a6c51af04fdb689e)
OMEGA Speedmaster Dark Side of the Moon “Black Black”- DSOTM - 311.92.44.51.01.005
This is a rare Omega Speedmaster Dark Side of the Moon "Black Black" watch, one of only 56 pieces made in this colorway.
- Condition: Excellent condition, very little signs of wear
- Case Diameter: 44mm
- Band Material:
- Movement Type:
![[WTS] Omega Speedmaster Professional Rubber strap with fold over clasp $500](https://external-preview.redd.it/eJ5kngWdNFHUme9RGEt4LJw0JOBzXsn9IA8DRREab4E.jpeg?auto=webp&s=3da254ad4064ab936f192cbc12f58761d722f866)
Omega Speedmaster Professional Rubber strap with fold over clasp $500
A rubber strap for an Omega Speedmaster Professional, purchased from Omega and used for about two months.
- Condition: Pre-owned with minor damage
- Material: rubber
- Strap Condition: pre-owned
- Damage Description: scratch on the clasp