Strap for Master Collection Big Date

The lug width (misura ansa) of the Longines Master Collection L2.648.4.51.7 is 20mm. This measurement represents the distance between the lugs at the point where the strap attaches to the case. Verifying this dimension when purchasing an aftermarket strap is essential to ensure a perfect and secure fit.

The best strap choice depends on intended use and personal preferences. For formal and classical contexts, we recommend vegetable-tanned alligator or smooth calf leather in brown or black tones. For more sporty applications, hydrophobic rubber maintains elegance and practicality. Shell cordovan represents a premium option for those seeking durability and natural patina development over time. On milanostraps.it you will find a curated selection of 20mm compatible straps, customisable in colour and stitching thread.

Strap replacement requires a spring bar tool to remove the pins securing the strap to the lugs. Position the tool in the small hole on the lug, press towards the centre to release the spring, and slide off the old strap. Repeat from the other side. For the new strap, align the pins with the lugs and push gently until the spring clicks into position. If preferred, Casati Milano offers mounting service by appointment.

Any strap with a 20mm lug width is compatible with the L2.648.4.51.7. On milanostraps.it you will find a curated collection of 20mm straps in various materials: alligator, calf, shell cordovan, rubber and NATO fabric. Each strap can be personalised in length (arm dimensions), colour tone and stitching thread to suit your style and wrist proportions.

The lifespan of a leather strap depends on material quality, frequency of use and maintenance. A high-quality calf or alligator strap, worn regularly but not daily, typically lasts 3-5 years. Shell cordovan, being more robust, can exceed 7-10 years. Straps crafted by milanostraps.it in vegetable tanning develop natural patina over time, improving aesthetically. Casati Milano guarantees 18 months on bespoke straps and recommends periodic maintenance (gentle cleaning and conditioning) to extend lifespan.