Strap for Admiral GMT Black Brown

The lug width of the Longines Admiral L3.668.4.56.3 is 22mm. This measurement refers to the internal distance between the two metal lugs (spring bar seats) that secure the strap to the case. It is essential to verify this dimension before purchasing an aftermarket strap, as an incorrect lug width (for example 20mm or 24mm) will not be compatible.

The best strap depends on usage and personal preference. For elegance, we recommend alligator with vegetable tanning or shell cordovan, which enhance the brushed stainless steel case. For versatile daily wear, quality calf leather in dark colours (cognac, black, slate grey) offers comfort and develops a rich patina over time. To emphasise the watch's original nautical identity, a NATO strap in heavyweight canvas—khaki or navy—is the authentic choice.

To change the strap, remove the two spring bars that secure it to the lugs. Use a dedicated spring bar tool to compress each pin and slide it free from its seat—work carefully to avoid scratching the case. Insert the new strap into the lugs, reinsert the spring bars, and confirm they are fully seated. Do not force: if a spring bar resists, lightly lubricate it with neutral silicone before attempting again.

Yes, quality aftermarket straps are fully compatible, provided they respect the 22mm lug width and correct spring bar diameter. Always verify the strap specifications before purchase. A handcrafted strap in premium leather with artisanal construction often offers superior quality, patina development, and longevity compared to the standard Longines factory strap.

A quality leather strap typically lasts 3 to 5 years under moderate daily use. Alligator with vegetable tanning and shell cordovan easily reach 5 to 7 years of service. Standard calf leather lasts 3 to 4 years. Longevity increases when the strap is alternated (not worn consecutively), kept away from prolonged moisture, and maintained regularly. Visible patina is not deterioration but natural ageing of the leather.