Rolex · Day-Date 40

Strap for Day-Date 40 Platinum - Baguette / White Roman

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
Reference228396tbr-0018
FamilyDay-Date 40
MovementRolex caliber 3255 hours, minutes, seconds | date, day | chronometer
Year2015
CasePlatinum

Recommended spring bar

Spring bars Rolex Daytona 116520 — 20mm steel

Technical match for lug width and diameter · lug 20 mm · Ø 1.5 mm · closed lugs

All Rolex spring barsOpen →

Straps for the Day-Date 40 228396tbr-0018

Selected for the 20 mm lug width · workshop selection

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The Day-Date 40 228396tbr-0018, seen from the bench

The Day-Date was introduced in 1955 as the world's first wristwatch to display the day and date in full at midnight. It features the automatic caliber 3255 with functions for hours, minutes, seconds, date and day of the week, certified as a chronometer. The case has 20mm lugs and the movement is equipped with an antimagnetic blue Parachrom hairspring.

Frequently asked questions

What is the lug width of the Rolex Day-Date 40 228396tbr-0018?

The Rolex Day-Date 40 reference 228396tbr-0018 has a lug width of 20 mm. This measurement is standardised across the entire Day-Date 40 family and is the key dimension to consider when selecting any aftermarket or replacement strap.

What is the best strap for the Rolex Day-Date 40 228396tbr-0018?

For a platinum 950 case such as that of the Day-Date 40 228396tbr-0018, the most suitable materials are alligator belly leather in midnight blue or slate grey, shell cordovan in burgundy or black, and vegetable-tanned leather that develops a personal patina over time. A brushed steel deployant clasp completes the pairing whilst maintaining visual coherence with the cold tones of platinum.

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

The strap on the Rolex Day-Date 40 is removed using a spring bar tool to disengage the spring bars from the case lugs. It is advisable to work on a soft surface to avoid scratching the platinum case. Those unfamiliar with the process can have the strap fitted by a watchmaker or by the Casati Milano atelier at the time of strap delivery.

Are there aftermarket straps compatible with the Rolex Day-Date 40 228396tbr-0018?

Yes, any strap with a 20 mm lug width is technically compatible with the Rolex Day-Date 40 228396tbr-0018. Milanostraps.it offers a curated selection of Italian artisan 20 mm straps in various materials and finishes, crafted to fit Rolex lugs geometrically with a taper to 16 or 18 mm at the buckle end.

How long does a leather strap last on a Rolex Day-Date 40?

The longevity of a leather strap depends on the material, care and frequency of use. A quality alligator or shell cordovan strap, with regular use and proper maintenance (avoiding direct water exposure and applying specialist leather conditioner every two to three months), can last between three and seven years while retaining structural and aesthetic integrity. Casati Milano straps carry an 18-month guarantee against manufacturing defects.

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