Omega · Speedmaster Moonwatch

Strap for Speedmaster Professional Mark II Plated

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter42 mm
ReferenceMD 145.034
FamilySpeedmaster Moonwatch
MovementOmega caliber 861 small seconds, hours, minutes | Chronograph
Year1972 - 1975/6
CaseStainless Steel

Recommended spring bar

Spring bars Omega 20mm — 1.8mm diameter

Technical match for lug width and diameter · lug 20 mm · Ø 1.8 mm

All Omega spring barsOpen →

Straps for the Speedmaster Moonwatch MD 145.034

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Speedmaster Moonwatch MD 145.034, seen from the bench

The Omega Speedmaster Moonwatch reference MD 145.034 is a mechanical chronograph certified for extravehicular activity during Apollo missions, worn on the Moon in July 1969. The Professional line embodies original construction philosophy: reliability, tactical legibility, and verified chronometric precision. Powered by the Omega 861 calibre with manual winding and vertical column wheel, the steel case measures 41.75 mm diameter with 14.9 mm thickness. Features squared lugs, domed plexiglass crystal, and 20 mm lug width designed for athletic wrists with robust passants and clip buckles. Lug-to-lug distance must measure exactly 20 mm for proper fit.

Frequently asked questions

What is the exact lug width of the Omega Speedmaster Moonwatch MD 145.034?

The lug width of the MD 145.034 is 20 millimetres, measured perpendicularly between the two horizontal lugs of the case. This width is specific to the Moonwatch Professional and is incompatible with 22mm straps. Verify your strap compatibility by measuring the distance between the lugs with a digital calliper.

Which strap material is best for the Omega Speedmaster Moonwatch?

Alligator is the preferred material to maintain the vintage aesthetic of the original Moonwatch: thin leather, natural tapered grain, patina that improves over time. For intensive daily use, dark brown calf leather offers superior durability and moisture resistance. NATO straps guarantee tactical versatility and quick change capability, while FKM rubber is mandatory if you practise water sports.

How do you change the strap on an Omega Speedmaster Moonwatch?

The MD 145.034 uses screw-down spring bars accessible from the case back. Remove the caseback with a fine flathead screwdriver, extracting the tiny barrels from the retaining holes. Extract the spring with a rounded-tip watchmaker's tweezers, replace the strap, reinstall the springs verifying absolute locking. If you do not possess the tools, entrust a certified Omega professional.

Is an aftermarket 20mm strap truly compatible with the Moonwatch MD 145.034?

Dimensional compatibility (20mm lug width) is a necessary but not sufficient condition. Omega spring bars have tight manufacturing tolerances and require replacement springs identical in diameter and hardness. Generic straps could cause lateral play or excessive pressure on the lugs. Choose specialized suppliers who test compatibility with the MD 145.034 before shipping.

How long does a leather strap last on an Omega Speedmaster Moonwatch worn daily?

A high-quality alligator strap lasts 3-5 years with daily wear and regular maintenance (monthly wet cleaning, natural air drying, no direct heat). Calf leather lasts 2-3 years. Shell cordovan exceeds 5 years if not frequently exposed to moisture. Actual lifespan depends on perspiration intensity, local climate, strap change frequency and washing habits. A replacement strap allows strategic rotation and extends overall lifespan.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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