Rolex · Datejust 31
Strap for Datejust 31 Stainless Steel Domed Diamond / Jubilee / Pink MOP
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 178344-0018
Selected for the 16 mm lug width
The Datejust 31 178344-0018, seen from the bench
Frequently asked questions
What is the lug width of the Rolex Datejust 31 ref. 178344-0018?
The lug width of the Rolex Datejust 31 reference 178344-0018 is 16 mm. This measurement is consistent across the entire Datejust 31 production line and determines compatibility with any aftermarket strap. For a clean fit against the Oyster case, straps with curved ends are strongly recommended to follow the profile of the lugs.
What is the best strap for the Rolex Datejust 31 178344-0018 with a mother-of-pearl dial?
For the Datejust 31 178344-0018 with a mother-of-pearl dial and white gold bezel, the most suitable options are vegetable-tanned alligator in ice white or stone grey tones, which create tonal continuity with the dial's cool reflections, or polished box-calf leather in deep bordeaux or midnight blue for an elegant contrast. Shell cordovan is an excellent choice for those prioritising durability and gradual, even ageing. A deployant clasp in steel or white gold completes the pairing while protecting the lugs.
How do you change the strap on a Rolex Datejust 31 178344-0018?
To replace the strap on the Rolex Datejust 31 178344-0018, a double-tip spring bar tool is required. The spring bars are compressed laterally by leveraging between the lug and the strap with the hook tip, then the strap is removed. The new strap with spring bars inserted is positioned between the lugs, compressing the bars until they click into place. Exercise extreme caution to avoid scratching the steel or white gold lugs. If in doubt, it is advisable to consult a watchmaker or the Casati Milano atelier.
Are there aftermarket straps compatible with the Rolex Datejust 31 178344-0018?
Yes, high-quality aftermarket straps compatible with the Rolex Datejust 31 178344-0018 are available. The key parameter is a 16 mm lug width with curved ends to match the Oyster case profile. Milano Straps offers a curated selection of handcrafted straps in alligator, calf leather, shell cordovan, and technical fabric, made specifically for this lug width, including spring bars and buckles in steel or gold PVD.
How long does a leather strap last on a Rolex Datejust 31?
The lifespan of a leather strap on a Rolex Datejust 31 depends on the material and conditions of use. A quality vegetable-tanned alligator strap, with proper care — periodic conditioning, rotation between multiple straps, and avoiding prolonged contact with water and perspiration — can last between 3 and 6 years while retaining structural integrity and developing a beautiful patina. Shell cordovan, owing to the density of the horse's gluteal muscle fibre, typically offers superior longevity. Standard calf leather straps have an average lifespan of 2 to 3 years under daily intensive use.
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

