Omega
Speedmaster Moonwatch MD 145.034— lug 20mm

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.

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.

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.

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.

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.