Strap for Master Collection 40 Moonphase Stainless Steel / Blue / Bracelet

The lug width of the Longines Master Collection L2.909.4.92.6 is 21mm. This is a rare configuration in contemporary horology. Correct measurement is taken by drawing a straight line between the two lateral mounting points of the case, beneath the lugs, where the strap seats.

The ideal strap depends on intended use. For formal and evening contexts, half-gloss alligator leather complements the steel case elegantly. Vegetable-tanned calf develops authentic patina over time. NATO canvas in 21mm offers daily versatility and colour variation. Shell cordovan, for those accepting a longer patination curve, delivers superior density and water resistance.

Strap change is performed by gently sliding the lateral steel pins (spring bars) that thread through the case lugs. Use a spring bar tool or specialised tool to depress the pin from one side, allowing the strap to slide free. Insert the new strap, align the holes, and depress the pin on the opposite side until it clicks into place. Always verify security before wearing.

Yes, provided the strap is specifically engineered for 21mm lug width. MilanoStraps offers handcrafted straps customizable in leather, NATO, and other materials, available for immediate dispatch or bespoke creation at Casati Milano atelier. Artisanal construction quality ensures longevity and aesthetic coherence with your timepiece's value.

A quality artisanal leather strap, with mindful maintenance, lasts approximately 3–5 years of daily wear. Longevity depends on: leather type (alligator > shell cordovan > calf), water exposure frequency, wrist transpiration, and periodic care. MilanoStraps straps in vegetable-tanned calf carry an 18-month warranty and may be restored at the Casati Milano atelier.