Strap for Horological Machine N°3 HM3 Frog X Blue

The MB&F Horological Machines 36.SVL.BU features a 20mm lug width. This measurement was deliberately selected to maintain optimal visual proportions of the 47mm sapphire case, preventing the strap from competing aesthetically with the HM3 calibre movement on display. For perfect compatibility, the strap's passages must accommodate the 20mm lug width with a tolerance of ±0.5mm.

The ideal strap depends on your personal aesthetic philosophy. Black or navy alligator represents the classical formal choice, emphasizing the constructive rigour of the movement. Shell cordovan in deep red offers instead chromatic depth and evolutionary patina over time. For those preferring contemporary aesthetics, a grey NATO canvas strap conveys modernity without functional compromise. An FKM rubber bracelet creates the most radical contrast, amplifying the conceptual nature of the timepiece.

Use a dedicated spring bar tool designed for high-end watches, positioning it perpendicularly to the lug pins. Apply gentle, consistent pressure whilst avoiding rotational movements that might compromise pin integrity. The new strap's passages must guide smoothly without excessive play: over-tight passages complicate pin insertion, whilst loose passages create lateral instability. For this particular model, professional installation by a qualified watchmaker is strongly recommended given the sensitivity of the sapphire case.

Absolutely. Quality artisanal aftermarket straps represent a genuine opportunity for customisation without compromise. The critical factor is verifying that the strap has been crafted by a specialist manufacturer with precise tolerances for 20mm lugs. Milano Straps curates a carefully selected collection of 20mm straps in alligator, cordovan, NATO, and rubber—all compatible with the 36.SVL.BU and ready for dispatch.

A quality artisanal alligator or cordovan strap, worn daily, maintains functional and aesthetic integrity between 18 and 36 months before requiring refurbishment. Longevity depends on environmental humidity, intensity of use, and maintenance regularity. Leather fears excessive moisture and chemical agents (aggressive perspiration, sunscreens): monthly cleaning with a slightly dampened cloth and quarterly conditioning with neutral creams substantially extends operational life. A canvas NATO strap, being synthetic, boasts superior durability, typically 3–5 years under moderate to intensive use.