Rolex · Datejust 31
Strap for Datejust 31 Stainless Steel Domed / Oyster / White Roman
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 178240-0031
Selected for the 16 mm lug width
The Datejust 31 178240-0031, seen from the bench
Frequently asked questions
What is the lug width of the Rolex Datejust 31 178240-0031?
The lug width of the Rolex Datejust 31 ref. 178240-0031 is 16 millimetres. This dimension represents the distance between the vertical lugs of the case and is essential for selecting a compatible strap. Use a digital calliper to verify this measurement internally, avoiding errors that would compromise the installation process.
Which strap is most suitable for the Rolex Datejust 31 178240-0031?
Alligator leather with vegetable tanning is the architectural choice recommended for the Datejust 31: the natural scale texture amplifies the luminosity of Oystersteel without competing visually. Alternatively, fine-grain calf (black or cognac) offers a more contemporary aesthetic, whilst for intensive daily use a cotton ballistic NATO strap ensures structural reliability.
How do you replace the strap on a Rolex Datejust 31?
Strap replacement requires extraction of the spring bars from the riveted or screwed case lugs. It is advisable to consult a specialist to avoid accidental scratches on the brushed lug surface. If the strap is fitted with a deployant clasp, the operation is simplified: open the buckle delicately and insert the new bars, verifying the absence of residual mechanical play.
Are compatible aftermarket straps available for the 16mm Datejust 31?
Yes, numerous artisanal producers manufacture straps specifically for the 16mm lug width. Milano Straps offers a dedicated collection with options in vegetable-tanned leather, alligator and synthetic materials, all bespoke for the Datejust 31 178240-0031 and equivalent models of the same family.
What is the average lifespan of a leather strap on a Rolex Datejust 31?
A high-quality artisanal leather strap with vegetable tanning has a lifespan of 4–7 years under regular use conditions, depending on climate, humidity and frequency of wear. Patina develops progressively within the first 12–18 months. Periodic maintenance (cleaning with damp cloth, rapid drying) significantly extends leather longevity and preserves fibre brilliance.
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

