Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel Domed / Oyster / Silver

Takes 16 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width16 mm
Case diameter31 mm
Reference178240-0022
FamilyDatejust 31
MovementRolex caliber 2235 hours, minutes, seconds | date | chronometer
CaseStainless Steel

Spring bar

Spring bars for Rolex

The right category for this model · choose the 16 mm size

Straps for the Datejust 31 178240-0022

Selected for the 16 mm lug width

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The Datejust 31 178240-0022, seen from the bench

The Datejust 31 is Rolex's reference model since 1945, the first wristwatch to integrate a date with instant jump. This 31mm version (ref. 178240-0022) features a smooth stainless steel bezel and Oystersteel case, housing the Rolex 2235 COSC-certified movement with Parachrom balance wheel. The 16mm lug width is specific to the Datejust 31 line and requires compatible aftermarket straps. Water resistant to 100 meters, it offers hours, minutes, seconds, and quick-set date function.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 reference 178240-0022?

The Rolex Datejust 31 ref. 178240-0022 has a lug width of 16mm. This measurement is specific to the Datejust 31 line and requires straps designed for this attachment, as the Oyster lug profile has a slightly tapered inner geometry that is not compatible with all generic 16mm straps.

What is the best strap for the Rolex Datejust 31 178240-0022?

For the steel Datejust 31 with a smooth bezel, a vegetable-tanned alligator strap is the most coherent choice given the case's formal character. Alternatively, box-grain calf leather suits daily wear, while high-grade vulcanised rubber offers water resistance without compromising aesthetics. All materials should be paired with a 16mm steel buckle or deployant clasp to maintain visual harmony with the Oystersteel case.

How do you change the strap on a Rolex Datejust 31?

To replace the strap on the Datejust 31, use a fine-tipped spring bar tool or a dedicated Rolex spring bar screwdriver. The 16mm spring bars are released by applying gentle inward pressure towards the case within the lug slot. Always work on a soft surface to avoid scratching the case, and ensure that replacement spring bars match the correct diameter — typically 1.5mm for this format.

Are there aftermarket straps compatible with the Rolex Datejust 31 178240-0022?

Yes, high-quality aftermarket straps are available specifically designed for the 16mm lug width of the Datejust 31. It is essential to choose manufacturers who respect the Oyster lug geometry, with appropriately curved and tapered ends. Milano Straps offers a curated selection of 16mm straps tested for compatibility with this reference, available in various materials and finishes.

How long does a leather strap last on a Rolex Datejust 31?

The lifespan of a leather strap depends on the material, care routine, and frequency of use. A quality vegetable-tanned alligator strap, kept away from water and excessive perspiration and treated periodically with a specific leather conditioner, can last between three and seven years while retaining structural integrity and a refined appearance. Box-grain calf leather has a similar lifespan but develops patina more readily. Milano Straps offers an 18-month guarantee covering manufacturing defects.

The next step

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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.

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