Strap for Master Collection Power Reserve

The lug width of the Longines Master Collection L2.666.4.78.6 is 20mm. This measurement is taken centre-to-centre between the two spring bar attachment points on the case. Any strap with 20mm lugs will be fully compatible with this model.

The ideal strap depends on your intended use. For formal elegance, we recommend genuine alligator in dark brown or black. For daily practicality, a vegetable-tanned calf leather with a gummed finish offers durability and natural patina development. If you seek chromatic versatility, a robust woven NATO in navy blue combines elegance with functionality. The choice ultimately reflects your personal aesthetic and primary wearing context.

The strap is changed by removing the spring bars—the small metal cylinders that secure the strap within the case lugs. Using a spring bar tool (often included with quality aftermarket straps), apply gentle downward pressure on one side of the spring bar until it releases from the lug. Repeat for the opposite side. Insert the new strap by aligning its lugs with the 20mm attachment points and press until the spring bar clicks into place.

Absolutely. The Longines Master Collection L2.666.4.78.6 accepts any strap featuring 20mm lugs. High-quality aftermarket straps do not damage the case and allow you to explore multiple aesthetic interpretations of the same watch. We recommend selecting premium leathers—alligator, shell cordovan, or vegetable-tanned calf—to ensure durability and visual coherence with the case's formal character.

A quality leather strap (alligator, vegetable-tanned calf, shell cordovan) typically lasts 3–5 years with daily wear, depending on the tanning method, sun exposure, and humidity levels. Vegetable-tanned leather ages beautifully and develops a rich patina. A robust woven NATO strap lasts 5–7 years. Periodic strap replacement is normal practice and desirable: it refreshes the watch's aesthetic without touching the case.