Rolex · Day-Date 40
Strap for Day-Date 40 White Gold - Diamond / Silver Quadrant
Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.
Lug width
Straps for the Day-Date 40 228349rbr-0004
Selected for the 20 mm lug width · workshop selection
Black Alligator Strap with Light Blue Edges€210
Black Alligator Strap with White Edges€210
Millenium Cognac Alligator Strap€270
Matte Blue Alligator Strap€270
Green Rubberized Alligator Strap with Ecru Tribal Stitching€185
The Day-Date 40 228349rbr-0004, seen from the bench
Frequently asked questions
What is the exact lug width of the Rolex Day-Date 40 ref. 228349rbr-0004?
The lug width (ansa width) of the Day-Date 40 ref. 228349rbr-0004 is precisely 20mm. This measurement represents the distance between the two spring bars that connect the strap to the case lugs. You can verify this by measuring with a digital calliper from the centre of the left lug pin to the centre of the right lug pin. Accurate measurement is essential to avoid purchasing incompatible straps.
Which strap is best suited for the Day-Date 40 white gold 228349rbr-0004?
For the Day-Date 40 in white gold, we recommend black alligator for maximum formality or dark brown alligator for daily wear. Both materials reflect the restrained elegance of white gold. Shell cordovan represents a more robust alternative, developing a deep burgundy patina over time. Avoid casual materials such as NATO: white gold demands aesthetic coherence.
How do you change the strap on a Rolex Day-Date 40?
The process is straightforward: use a spring bar tool to gently press downward on the left lug pin of the current strap, removing the strap from one side. Repeat on the right side. Insert the new strap's spring bars into the case lugs, ensuring the bars are fully seated. Always work over a soft surface to prevent scratching the white gold case.
Is an aftermarket 20mm strap compatible with the 228349rbr-0004?
Yes, any strap with a 20mm lug width is physically compatible with the Day-Date 40 ref. 228349rbr-0004. Physical compatibility does not guarantee aesthetic harmony, however. An artisanal strap in quality alligator or cordovan enhances the value of your Rolex, whilst generic straps may compromise the watch's visual balance.
How long does a natural leather strap last on a Rolex Day-Date 40?
The lifespan of a leather strap depends on material quality and usage patterns. Quality alligator has an average life of 4–6 years with moderate daily wear. Shell cordovan, owing to its dense fibre structure, can last 8 years or more. Vegetable-tanned calf leather ages visibly, typically requiring replacement after 3–5 years. Key factors: sunlight exposure, humidity, wear frequency, and personal perspiration. A well-maintained alligator strap can reach 7–8 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.
Request an appointment →Casati Milano · Via XX Settembre 15, Milan · by appointment only

