Strap for Datejust 31 White Gold Diamond / Grey

The lug width (ansa) of the Rolex Datejust 31 278289rbr-0014 is 16 millimetres. This measurement is determined by calculating the internal distance between the two case lugs where the strap attaches. It is essential not to confuse this dimension with the case width (7.4mm): a compatible strap must have exactly 16mm width to fit correctly into the attachment bars without lateral movement or play.

For the Datejust 31 278289rbr-0014 in white gold, alligator is the most natural choice: its characteristic grain pattern dialogues perfectly with the case's preciousness and develops a deep patina over time. Alternatively, shell cordovan offers a smoother surface with a burgundy tone that complements white gold beautifully. Vegetable-tanned calf leather guarantees softness and a golden patina that emerges through daily wear. For sportier contexts, silk or raw cotton NATO straps in light tones (white, beige) represent an elegant and versatile option.

Strap replacement requires a spring bar tool. Gently insert the tool into the small lateral hole of the lug, pushing the retraction pin inward to release the spring. Once the first attachment is freed, pull the strap outward. Repeat the operation on the other side. To install the new strap, insert the spring bar attachments into the corresponding case holes and press until the springs engage again. If uncertain, consult a certified watchmaker or the Casati Milano service.

Strap length depends on wrist circumference and personal wearing preferences. Generally, for a Datejust 31, straps with a total length between 200 and 210 millimetres (measured from the first adjustment hole) are recommended, ensuring comfortable wear with approximately 4-5 adjustment holes toward closure. For smaller wrists, length can be customised with Casati Milano, whilst online 16mm straps are proportioned for average anatomy.

A natural leather strap (alligator, cordovan, or vegetable-tanned calf) typically lasts between 4 and 8 years, depending on usage intensity and maintenance. The leather wears primarily where it flexes at the buckle and adjustment holes. Casati Milano straps are crafted from superior quality leathers and include an 18-month warranty against manufacturing defects. To extend durability, alternate the strap weekly and avoid prolonged water exposure. Over time, natural patina becomes part of the piece's beauty.