Strap for Speedmaster 57 Master Chronometer 40.5 Stainless Steel / Red / Bracelet

The lug width of this model is 20 millimetres. This dimension corresponds to the distance between the inner shoulders of the case attachment pins, measured horizontally. It is essential to verify that any strap purchased strictly adheres to 20 mm, otherwise it will not fit correctly.

The choice depends on your intended use. For formal elegance, black alligator or cognac cordovan deliver maximum aesthetic impact. For everyday versatility, vegetable-tanned calf in brown or burgundy balances luxury and practicality. For sports and maritime contexts, vulcanized rubber or NATO faithfully preserve the technical identity of the model.

The procedure requires two tools: a spring bar tool and a small fine-tipped tweezers. Position the strap flat, insert the spring bar tool into the lateral slot of the lug, apply gentle pressure to compress the internal spring of the pin, and once released, slide the pin out. Repeat for the second side. Reverse installation for the new strap, verifying that the pins are fully inserted.

Yes, provided the strap is designed for 20 mm lug width. Superior quality artisanal straps—selected leather, reinforced stitching, certified deployant clasps—deliver results superior to OEM straps and enrich the tactile and visual experience of the watch.

A quality leather strap (alligator, cordovan, calf) lasts between 4 and 8 years depending on use, climatic conditions and maintenance. Exposure to sun, sweat and humidity accelerates ageing. Atelier straps such as Casati Milano offer 18-month warranty against manufacturing defects and provide maintenance guidance to extend longevity.