Rolex
Datejust 31 178288-0085— lug 16mm

The lug width (misura ansa) of the Rolex Datejust 31 178288-0085 is 16mm. This is the distance between the two spring bars that connect the strap to the case lugs. It is a Rolex standard specific to the 31mm model and is essential for ensuring a perfect fit without play or gaps.

For a Datejust 31 in yellow gold, alligator (Mississippi or Nile) is the classic and reliable choice, available in brown, cognac, or burgundy tones. Shell cordovan is exceptional for those seeking durability and a unique natural patina. Vegetable-tanned calf offers softness and sustainability, developing character over time. Structured rubber is ideal for everyday versatility.

The strap is changed by extracting the spring bars from the case lugs using a dedicated spring bar tool. Position the tool in the small groove of the bar, push toward the centre of the case and the bar retracts, allowing extraction. Repeat on the other side, then position the new strap by aligning the holes and re-inserting the spring bars until they click into place.

Yes, provided the strap is constructed for a 16mm lug width. Compatibility depends on the exact width of the lug attachment points (16mm) and the build quality—whether leather, rubber, or metal—must be of a standard comparable to Rolex to avoid compromising the watch's aesthetics. We recommend bespoke artisanal straps made to specification to guarantee precision in proportions and finishing.

A quality leather strap (alligator, shell cordovan, vegetable-tanned calf) lasts between 3 and 7 years depending on daily use and maintenance. Alligator and shell cordovan are more resistant and can exceed 5–7 years. Critical factors are: sun exposure, humidity, perspiration, and frequency of wear. Proper storage (away from direct light and damp conditions) significantly extends strap life. Casati Milano straps include an 18-month warranty against manufacturing defects.