Rolex · Datejust 31
Strap for Datejust 31 Stainless Steel Domed / Jubilee / White
Takes 16 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.
Lug width
Straps for the Datejust 31 178240-0015
Selected for the 16 mm lug width
The Datejust 31 178240-0015, seen from the bench
Frequently asked questions
What is the lug width of the Rolex Datejust 31 178240-0015?
The lug width of the Rolex Datejust 31 178240-0015 is 16 millimetres. This dimension is measured between the inner points of the two lateral lugs and is proportionally designed for the 31mm case. Respecting this specification is essential to ensure proper strap installation without mechanical stress on the lugs.
Which strap is most suitable for the Rolex Datejust 31 178240-0015?
For the stainless steel Datejust 31, Mississippi alligator is the most harmonious choice: its regular grain and silvery patina reflect the 904L case finishing. American shell cordovan develops an amber patina that brings warmth, whilst vegetable-tanned Italian calf offers natural ageing and visible character for those who appreciate it.
How do you change the strap on a Rolex Datejust 31?
Changing the strap on a Datejust 31 requires an appropriate spring bar tool. Position the watch with the lugs facing upward, insert the tool into the lateral access hole of the lug, gently lift the internal spring, and withdraw the case bar. Repeat on the other side. The new strap must have a 16mm lug width for secure, play-free installation.
Is the Rolex Datejust 31 178240-0015 compatible with quality aftermarket straps?
Yes, provided the lug width is precisely 16 millimetres. Artisanal straps in alligator, shell cordovan, calf, and vegetable-tanned leather are compatible. It is advisable to verify that the strap has been constructed with quality spring bars, as the Rolex requires precise manufacturing tolerances to prevent damage to the stainless steel 904L lugs.
How long does a leather strap last on a Rolex Datejust 31?
The lifespan of a leather strap depends on usage and construction quality. A premium alligator or shell cordovan strap, with proper maintenance (regular cleaning, protection from excessive moisture), can last 5–8 years. A softer vegetable-tanned calf typically offers 3–5 years of useful life. Visible ageing of the leather is an intentional characteristic, not a defect.
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

