Strap for Master Collection 40 Chronograph Calendar Stainless Steel / Yelllow Gold / Silver / Bracelet

The lug width of the Longines Master Collection L2.673.5.78.7 is exactly 21mm. This dimension is specific to this model and represents the distance between the inner shoulders of the horizontal pins. A 20mm strap will not provide proper fit, whilst a 22mm strap will not enter the lugs. To verify compatibility, measure the internal width of the case lugs with a calliper or consult an authorised Longines service centre by providing the serial number.

Alligator is the choice of excellence for this model: natural scales, shaped and finished with satin refinement, enhance the chromatic contrast between yellow gold and steel. A chocolate brown alligator adds warmth to the wrist, whilst a beaver grey creates harmony with the steel. For those preferring versatility, vegetable-tanned calf develops natural patina over time. A ballistic canvas NATO in navy blue or British Racing Green maintains elegance without rigidity, ideal for a casual register. Avoid generic synthetic materials.

Strap replacement requires precision. Position the watch on a rubber pad with the case facing downward. Using a dedicated spring bar tool, gently press the horizontal pin downwards from the lower side, creating space to extract the old strap end. Repeat on the other side. Insert the new 21mm strap, ensuring that the lug ends sit uniformly in the pins. If unfamiliar with the procedure, entrust the task to a qualified watchmaker: the L2.673.5.78.7 deserves attention to detail.

Yes, provided they strictly respect the 21mm lug width specification. MilanoStraps offers a curated selection of compatible straps in alligator, calf, NATO and rubber, crafted with Italian artisanal standards. Each strap can be customised in dimensions, initials and choice of stitching thread. For a comprehensive service, the Casati Milano atelier creates bespoke straps with personal selection of leathers and delivery with 18-month warranty.

A quality artisanal leather strap lasts on average 5–7 years with regular wear. Longevity depends on several factors: frequency of use, exposure to moisture and UV rays, and quality of tanning. An alligator with vegetable tanning develops protective patina naturally, extending service life. Calf requires periodic maintenance with products designed for luxury footwear. Inspect the strap every 2–3 years, verifying fibre elasticity and stitching integrity. MilanoStraps offers an 18-month warranty on artisanal straps and provides support for eventual replacements.