Rolex
Datejust 31 178158-0051— lug 16mm

The lug width of the Rolex Datejust 31 178158-0051 is 16 millimetres. This is the space that a replacement strap must occupy between the two lugs of the Oyster case. This dimension is specific to this particular configuration and is not interchangeable with other Rolex Datejust models featuring different case diameters.

For the yellow gold Datejust 31 178158-0051, alligator in dark brown, vegetable-tanned calf in cognac, or shell cordovan are recommended. Dark brown or black alligator creates the classic, timeless contrast. For tonal harmony, medium cognac echoes the warm temperature of the gold. Pure black communicates contemporary sophistication and drama. The choice depends on personal style and context of use.

Changing a strap on a Rolex requires specific tools: a spring bar tool or small precision lever. Insert the tool into the lateral hole of the case lug, compress the internal spring, and gently extract the old strap. The new strap is inserted by sliding the spring into the opposite hole until it clicks into place. We recommend performing this operation on a soft surface in good light. Alternatively, Casati Milano offers professional strap-change service by appointment.

Yes, any strap with a 16-millimetre lug width is compatible with the Datejust 31 178158-0051, provided the spring bar is the correct length and diameter. Milano Straps bespoke straps are constructed specifically for this lug width. We recommend selecting materials and colours that respect the classical elegance of the yellow gold case, avoiding visual competition with the precious metal.

The lifespan of a leather strap depends on material quality, frequency of use, and environmental conditions. A high-quality artisanal alligator or vegetable-tanned calf strap typically lasts 3–5 years with daily wear, extending to 7–10 years with occasional use and proper maintenance. Prolonged exposure to moisture, perspiration, and UV radiation shortens strap life. Milano Straps are guaranteed 18 months against manufacturing defects and can be refurbished or replaced through Casati Milano atelier.