Longines · La Grande Classique

Strap for La Grande Classique Tonneau 35 Diamond

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter35 mm
ReferenceL4.789.0.51.4 (aka: L47890514)
FamilyLa Grande Classique
MovementLongines caliber L420 hours, minutes
CaseStainless Steel

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the La Grande Classique L4.789.0.51.4 (aka: L47890514)

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The La Grande Classique L4.789.0.51.4 (aka: L47890514), seen from the bench

The Longines La Grande Classique Tonneau 35 Diamond L4.789.0.51.4 is a 35mm stainless steel watch embodying Swiss watchmaking philosophy through proportional purity and restrained design. It features the Longines caliber L420 quartz movement and a minimalist dial free of superfluous decoration. The 20mm lug width is precisely calibrated to maintain visual balance between case and strap.

Frequently asked questions

What is the exact lug width of the Longines La Grande Classique L4.789.0.51.4?

The lug width of this model is 20 millimetres. This dimension represents the internal width between the watch's lugs. To verify, position a ruler perpendicularly across the lugs: the internal distance must be 20 mm. This standard allows for a wide selection of compatible straps available online and in specialist ateliers.

Which strap is recommended for the Longines La Grande Classique L4.789.0.51.4?

Crocodile leather in brown or black represents the most refined choice, offering elegance without competing with the watch's understated case. For natural patination, calf leather with vegetable tanning is ideal: it develops personal character over time. Shell cordovan is reserved for those who appreciate rarity and extraordinary wear resistance. NATO and rubber options offer versatility for informal or sports use.

How do I change the strap on the Longines La Grande Classique L4.789.0.51.4?

The process requires a spring bar tool. Position the watch face-down on a soft surface. Insert the tool under the lug pin and lift gently to release it from its housing, then remove the old strap and insert the new one. Ensure the pin is properly aligned before pressing it back. If inexperienced, consult a specialist atelier.

Can I use aftermarket straps with the Longines La Grande Classique L4.789.0.51.4?

Yes, any strap with a 20mm lug width is compatible with this model. You'll find a wide selection of reputable brands online, from satin calf to crocodile, including more casual options such as NATO and rubber. The key is verifying that the declared width genuinely corresponds to 20 mm.

How long does a leather strap last on the Longines La Grande Classique L4.789.0.51.4?

Durability depends on material and usage patterns. Quality calf leather with vegetable tanning lasts 3-5 years with regular wear; shell cordovan easily reaches 10+ years. Crocodile offers intermediate resistance (5-7 years). Factors such as sun exposure, perspiration, and humidity influence ageing. Specialist ateliers offer 18-24 month warranties and periodic restoration services to extend lifespan.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

Request an appointment →

Casati Milano · Via XX Settembre 15, Milan · by appointment only