Strap for Master Ultra Thin Moon Stainless Steel / Silver / Alligator

The lug width of the Jaeger-LeCoultre Master Ultra Thin 1368420 is 21mm. This measurement corresponds to the internal distance between the two lugs on the case where the strap attaches. It is essential to verify that any aftermarket strap has this exact width to ensure proper fit and structural compatibility with the case lugs.

For the Master Ultra Thin 1368420, we recommend straps in alligator, shell cordovan, or vegetable-tanned calf leather. Alligator offers natural texture that enhances the steely sobriety of stainless steel; shell cordovan guarantees durability and lustre that develops over time; vegetable-tanned calf develops a patina that improves with age. All straps must be 21mm and preferably fitted with a stainless steel deployante buckle for security and comfort.

To change the strap on the Master Ultra Thin 1368420, you must remove the spring bars connecting the strap to the case lugs. Use a dedicated spring bar tool to compress the bars and slide them out of their slots. Insert the new 21mm strap into the upper lug, align the spring bar, then press until you hear a secure click. Repeat for the lower lug. We recommend entrusting this operation to a professional watchmaker to avoid scratching the case.

Yes, aftermarket straps in 21mm width are fully compatible with the Master Ultra Thin 1368420, provided the lug width is exact and the spring bars are correctly aligned. Milanostraps.it offers a selection of artisanal leather straps in 21mm: alligator, shell cordovan, vegetable-tanned calf, and rubber. All straps are tested for precise fit and supplied with an 18-month warranty against manufacturing defects.

The lifespan of a natural leather strap depends on frequency of use and material. A vegetable-tanned calf strap typically lasts 3–5 years with daily wear; shell cordovan can last 5–7 years thanks to its greater fibre density; alligator falls between the two. Natural leather ages, patinas, and develops character: creases and wear are signs of nobility, not defect. Straps from Casati Milano and milanostraps.it are crafted from premium leathers and age gracefully. It is possible to have a worn strap restored or regenerated by a specialist leather artisan.