Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel Domed Diamond / Oyster / Black - Diamond

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
Reference178344-0030
FamilyDatejust 31
MovementRolex caliber 2235 hours, minutes, seconds | date | chronometer
CaseWhite 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 178344-0030

Selected for the 16 mm lug width

All 16 mm straps →

The Datejust 31 178344-0030, seen from the bench

The Rolex Datejust 31 reference 178344-0030 is a 31mm watch in Rolesor, combining Oystersteel and 18-karat white gold, with a diamond-set dial and fluted white gold bezel. It houses the Rolex caliber 2235, an automatic movement with Perpetual rotor certified chronometer by COSC, displaying hours, minutes, seconds, and date via triple calendar mechanism at 3 o'clock. The Oyster case is water-resistant to 100 meters with sapphire crystal and anti-reflective treatment. The lug width is 16mm, a non-standard size requiring precise measurement between the case lugs.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 178344-0030?

The lug width of the Rolex Datejust 31 178344-0030 is 16mm. This measurement is taken as the internal distance between the two case lugs using a digital calliper. It is a non-standard size compared to the 20mm found on men's Datejust models, so verifying this dimension before purchasing any aftermarket strap is essential.

What is the best strap for the Rolex Datejust 31 178344-0030?

For the Datejust 31 178344-0030 in Rolesor with a diamond-set bezel, polished alligator is the most technically coherent choice: the scale texture reflects light in a manner consistent with the white gold, creating visual continuity. Alternatively, vegetable-tanned calfskin develops a natural patina that contrasts elegantly with the stable metallic finish of the case. For sporting or summer use, a vulcanised rubber strap is recommended to preserve the Oyster waterproofing.

How do you change the strap on a Rolex Datejust 31 178344-0030?

To replace the strap on the Datejust 31 178344-0030, a 1.8mm spring bar tool compatible with Rolex lugs is required. Insert the tool into the lug hole, compress the spring bar, and slide the strap free. Care must be taken to avoid scratching the case: it is advisable to protect the bezel with PTFE tape and work on an anti-static mat. If you are not experienced with this procedure, it is preferable to consult a watchmaker.

Are there aftermarket straps compatible with the Rolex Datejust 31 178344-0030?

Yes, high-quality aftermarket straps compatible with the Rolex Datejust 31 178344-0030 are available, provided they feature a precise 16mm lug width attachment. Milanostraps.it offers a selection of handcrafted straps produced to this exact specification, in various materials and finishes. It is essential that the manufacturer explicitly confirms compatibility with the 16mm lug size and that the strap length is appropriate for the wearer's wrist circumference.

How long does a leather strap last on a Rolex Datejust 31 178344-0030?

The lifespan of a leather strap depends on the quality of the hide, the tanning process, and daily use. A first-grade alligator or shell cordovan strap, properly maintained, can last between 3 and 6 years with regular wear. Vegetable-tanned calfskin typically has a shorter lifespan of 2 to 4 years, though it develops a distinctive patina over time. Avoiding prolonged contact with water and perspiration, and applying a silicone-free natural conditioner periodically, will significantly extend the strap's life.

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