Strap for Master Collection 40mm Annual Calendar Stainless Steel / Blue / Alligator

The lug width of the Longines Master Collection L2.910.4.92.0 is 21mm. This measurement represents the linear space between the two case lugs where the strap attaches. Accurate measurement with callipers is essential to ensure the strap is compatible and does not cause lateral play.

For the Master Collection L2.910.4.92.0, alligator is the most elegant choice, with its distinctive scale texture that complements the stainless steel case beautifully. Fine-grain calf leather offers softness and superior drape, whilst vegetable-tanned leather develops a natural patina over time. For more active use, FKM rubber or Tropic rubber are recommended.

Strap replacement requires a dedicated pin remover tool to extract the lugs connecting the strap to the case. Position the watch face-down on a soft cloth, locate the small pins at each end of the case, insert the pin remover from the outside inward, and apply steady pressure. Repeat for the second pin. The new strap is inserted in reverse, ensuring the pins are fully seated.

A 21mm strap is compatible with any watch featuring the same lug width. Other brands' models (Omega, IWC, Rolex) with 21mm lugs will accept the strap, though total length may vary depending on case diameter. It is advisable to confirm desired length before ordering.

The lifespan of a leather strap depends on usage intensity and tanning quality. A vegetable-tanned alligator strap lasts 3 to 7 years of daily wear, developing a noble patina. Fine-grain calf leather has similar longevity. Rubber straps resist wear longer (7-10 years) but lose elasticity over time. A formal strap worn occasionally may last 10-15 years.