Strap for La Grande Classique Tonneau 35 Diamond

The lug width of the Longines La Grande Classique L4.789.0.87.6 is precisely 20 millimetres. This measurement is critical for strap compatibility: it must be measured between the two spring bars (lugs) that connect the strap to the case. A strap of lesser or greater width will not fit correctly.

Given the formal severity of this model, we recommend superior-grade alligator with vegetable tanning, coarse-grain calf (peccary type), or shell cordovan. These materials maintain aesthetic coherence with the brushed steel case. Avoid fabric straps, rubber, or polished leather, which would betray the classical character of the piece.

The strap is changed by removing the spring bars (lugs) from the lug holes. Use a spring bar removal tool or a pointed instrument to apply light lateral pressure on the spring bar, extracting it from the lug. Position the new strap and reinsert the spring bar until it clicks into place. Avoid violent tugging, which could damage the lug holes.

Yes, the 20mm width is rare in the mass market but available from specialist strap makers. MilanoStraps offers a curated selection dedicated to 20mm widths, customisable in material, colour, and personal dimensions. The lug width remains invariably 20 millimetres for the L4.789.0.87.6 model.

A natural leather strap (alligator, calf, cordovan) with vegetable tanning has a useful life of 3–5 years with regular wear and moderate maintenance. Exposure to sweat, frequent rain, and direct sunlight shortens the lifespan. A strap with an 18-month warranty represents a standard of artisanal reliability. Periodic rotation with a second strap extends overall longevity.