Rolex
Datejust 31 178241-0061— lug 16mm

The Rolex Datejust 31 reference 178241-0061 features a 16mm lug width. This width is the standard for all 31mm Datejust ladies' models and must be respected precisely in any replacement strap. Even minimal tolerance variations cause play on the crown and accelerated hinge wear.

For this reference, we recommend Mississippi alligator with regular grain, or extraordinary shell cordovan that develops beautifully alongside rose gold. The leather must respect the dress-watch nature of the piece: avoid NATO or rubber, reserved for casual wear. Vegetable-tanned calf remains a valid alternative for daily use whilst maintaining formal elegance.

The Datejust is fitted with a Rolex deployant clasp: it requires simple pressure on the lateral lever. Remove the strap by applying pressure, insert the new strap into the lugs ensuring alignment and perpendicularity, then close the clasp. If the new strap does not seat with fluid movement, the lugs may not be perfectly squared at 16mm: avoid forcing.

Compatibility requires three conditions: 16mm lug width, lugs squared to 90 degrees, and thickness consistent with the Rolex deployant clasp. A poorly squared strap generates instability on the crown and wear. Casati Milano produces straps with artisanal tolerances within ±0.1mm, guaranteeing perfect fit on all 31mm Datejust models.

With moderate use (worn 3-4 days per week), alligator or shell cordovan lasts 4-6 years. Vegetable-tanned leather lasts 3-4 years. Longevity depends on ambient humidity, cleaning frequency and sun exposure. A strap stored in a case with silica gel ages more slowly. Casati Milano guarantees 18 months against manufacturing defects on every piece.