Rolex · Datejust 31

Strap for Datejust 31 Rolesor Fluted Diamond / Oyster / Silver Computer

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
Reference178313-0034
FamilyDatejust 31
MovementRolex caliber 2235 Hours, Minutes, Seconds | Date | Chronometer
CaseYellow Gold, Stainless Steel

Spring bar

Spring bars for Rolex

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

Straps for the Datejust 31 178313-0034

Selected for the 16 mm lug width

All 16 mm straps →

The Datejust 31 178313-0034, seen from the bench

The Rolex Datejust 31 ref. 178313-0034 belongs to one of watchmaking's longest-running lineages, introduced in 1945 as the first wristwatch with a date window at 3 o'clock. This 31mm two-tone model combines Oystersteel and 18-karat yellow gold with a fluted bezel, powered by the Rolex caliber 2235 automatic movement certified chronometer by COSC with approximately 48 hours power reserve. The case measures 31mm in diameter with a 16mm lug width, featuring a screw-down crown and case back that ensure water resistance to 100 meters.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 178313-0034?

The Rolex Datejust 31 reference 178313-0034 has a lug width of 16mm. This measurement is certified by Rolex and should be verified with a digital calliper before purchasing any aftermarket strap. Even a one-millimetre discrepancy will render the strap incompatible with the case lugs.

What is the best strap for the Rolex Datejust 31 178313-0034?

For the steel and yellow gold Datejust 31, the most suitable straps are alligator belly with a scaled grain for formal occasions, vegetable-tanned calfskin for daily wear with natural patina development, or shell cordovan for a compact texture and understated sheen. All options must feature curved ends to fit correctly within the 16mm lugs.

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

To replace the strap on the Datejust 31, use a spring bar tool — either lever or push-pin type — to release the spring bars from the lugs. A nylon-tipped tool is recommended to avoid scratching the case or gold lugs. The operation is fully reversible and does not require a watchmaker, but should be performed carefully.

Are there aftermarket straps compatible with the Rolex Datejust 31 178313-0034?

Yes. Several artisan manufacturers, including Milano Straps, produce straps compatible with the 16mm curved-end profile of the Datejust 31. It is essential to specify the exact model when ordering to ensure the correct lug curvature. Straps listed on milanostraps.it are designed for this specific geometry.

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

The lifespan of a leather strap depends on the material and maintenance. A high-quality alligator strap, handled with care and stored properly, can last between three and six years. Vegetable-tanned calfskin offers a similar lifespan with the added benefit of developing a personal patina. Shell cordovan is the most durable of traditional leathers. Prolonged exposure to water, perspiration, and direct sunlight should be avoided.

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