Rolex · Day-Date 40

Strap for Day-Date 40 White Gold / Meteorite - Baquette

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

Lug width20 mm
Case diameter40 mm
Reference228239-0055
FamilyDay-Date 40
MovementRolex caliber 3255 hours, minutes, seconds | date, day | chronometer
Year2018
CaseWhite Gold

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Straps for the Day-Date 40 228239-0055

Selected for the 20 mm lug width · workshop selection

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The Day-Date 40 228239-0055, seen from the bench

The Day-Date 40 represents the evolution of the classic Rolex presidential watch with a 40mm case. It is powered by the automatic caliber 3255 certified chronometer with indication of hours, minutes, seconds, date and day of the week. It features 20mm lugs and maintains the distinctive functions that have characterized this collection since 1956.

Frequently asked questions

What is the lug width of the Rolex Day-Date 40 reference 228239-0055?

The lug width of the Rolex Day-Date 40 228239-0055 is 20.00 millimetres. This dimension is standardised across the model and determines compatibility with any aftermarket strap. To verify the measurement, position a measuring tool between the internal edges of the spring bar attachments on both lugs.

Which strap material is most suitable for a Day-Date 40 in white gold?

Alligator leather remains the most aesthetically coherent choice for white gold, owing to its natural texture and the patina it develops with age. Vegetable-tanned calf represents a functional alternative for daily wear, as it breathes more effectively and acquires character over time. For formal evening occasions, deep black alligator elevates the overall perception of the watch.

How do you change the strap on a Day-Date 40?

Changing the strap on a Rolex Day-Date 40 requires a spring bar tool to gently extract the spring that fastens the lug to the case. Position the tool in the small notch of the spring, press laterally and lift outward. Repeat for both lugs. Insert the ends of the spring into the holes of the new strap's lug width and secure to the case. Avoid forcing: Rolex components tolerate millimetric precision, not haste.

Is it safe to use an aftermarket strap that is compatible?

Yes, provided the lug width conforms to 20.00 millimetres and the build quality is certified. An alligator or vegetable-tanned calf strap produced by qualified craftsmen does not compromise the watch's value; rather, it personalises it. However, avoid unknown manufacturers: a poorly constructed strap can damage the case lugs. Casati Milano guarantees 18 months against manufacturing defects.

How long does a leather strap last on a watch worn daily?

An alligator or quality calf strap, with ordinary maintenance (periodic cleaning and drying after bathing), maintains structural integrity for 3–4 years of daily use. A vegetable-tanned strap ages more visually admirably than an industrially produced one, developing controlled creasing that increases its character. The spring bar itself will wear regardless and should be replaced after 4–5 years, independent of the strap's condition. Exposing the strap to persistent moisture (frequent showers, swimming) reduces durability to approximately 2 years.

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.

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