Rolex · Datejust 31
Strap for Datejust 31 Stainless Steel/ Rose Gold / Diamond / Grey - Roman / Jubilee
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 278381rbr-0030
Selected for the 16 mm lug width
The Datejust 31 278381rbr-0030, seen from the bench
Frequently asked questions
What is the lug width of the Rolex Datejust 31 Ref. 278381rbr-0030?
The lug width (misura ansa) of the Rolex Datejust 31 278381rbr-0030 is 16 millimetres. This measurement refers to the internal distance between the two screw holes on the lug shoulder. You can verify this by positioning a digital calliper perpendicular to the holes, excluding the external lips of the lug itself. This 16mm standard is specific to this 31mm case and is essential for ensuring mechanical and aesthetic compatibility with aftermarket straps.
What is the best strap choice for the Rolex Datejust 31 278381rbr-0030?
The optimal strap depends on your personal style and intended use. For formal elegance, we recommend cognac or black alligator with stainless steel deployante: the natural grain of the leather enhances the Everose-steel combination. For daily wear and longevity, vegetable-tanned calf in warm tones (dark beige, hazelnut) develops natural patina over time. For versatility, a British-woven NATO in grey or navy blue allows rapid changes. Your choice should reflect the warm tone of the Everose, avoiding overly cold contrasts.
How do I correctly change the strap on this Rolex?
To change the strap on a Rolex Datejust 31, you need two essential tools: a quality spring bar tool and good lighting. Position the watch so the lug faces you. Insert the flat tip of the spring bar tool into the small hole at the end of the spring, gently compress the spring downward, and pull the old strap away from the lug. Repeat on the other side. Then insert the new strap's spring bars into the lug holes, ensuring the spring is fully seated. Check that the strap is secure by pulling gently. Avoid forcing movement; smooth action indicates correct alignment.
Is an aftermarket strap compatible with the Rolex Datejust 31 278381rbr-0030?
Yes, all straps with a 16mm lug width are mechanically compatible with the Datejust 31 278381rbr-0030, provided they use standard spring bar specifications. However, aesthetic compatibility is equally important: we recommend selecting leather thickness and colour that respect the 31mm case proportions and the Everose-steel contrast. Overly rigid leather or unnatural dark tones can disrupt visual balance. Milano Straps curates a selection of 16mm straps specifically designed for this model.
What is the average lifespan of a natural leather strap on a watch like the Datejust 31?
A quality leather strap (alligator, calf, vegetable-tanned Shell Cordovan) under daily use has an average lifespan of 3–5 years before replacement becomes necessary. Duration depends on climate, frequency of wear, sun exposure, and humidity. Natural leather ages and gradually thins, especially in the flexion area near the buckle. Good maintenance—drying after water exposure, avoiding prolonged direct heat, rotating with other straps—significantly extends durability. Milano Straps provides straps with an 18-month warranty against manufacturing defects; natural leather wear is considered aesthetic evolution, 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

