Rolex
Datejust 31 178158-0084— lug 16mm

The Rolex Datejust 31 ref. 178158-0084 has a lug width of 16mm. This is a non-standard measurement typical of mid-sized Datejust models (31mm diameter). To verify it, measure the internal distance between the two lugs at the strap attachment point using a digital calliper.

For an 18-carat yellow gold case such as that of the Datejust 31 ref. 178158-0084, a smooth alligator strap in cognac or tobacco is the most technically coherent choice: the regular grain and natural patina amplify the warm tone of the precious metal. Vegetable-tanned calf leather suits daily use, whilst vulcanised rubber is recommended in sporting or aquatic contexts.

To replace the strap on the Rolex Datejust 31, use a 1.5mm precision spring bar tool or lever screwdriver to remove the 16mm spring bars securing the strap to the lugs. Rest the case on a protective cushion and work carefully to avoid scratching the yellow gold lugs. If in doubt, the operation can be carried out by the Casati Milano atelier.

Yes. Aftermarket straps with a 16mm lug width and standard spring bars are compatible with the Rolex Datejust 31 ref. 178158-0084. Milano Straps offers a selection of handcrafted straps in alligator, calf leather, shell cordovan, rubber and NATO, made to measure for this lug width, with buckle and keeper calibrated to 16mm.

The lifespan of a leather strap depends on the material and maintenance: a quality alligator strap with vegetable tanning, kept dry and periodically conditioned with a specific cream, can last between 3 and 7 years with regular use. Vegetable-tanned calf leather has a similar lifespan but greater sensitivity to moisture. Shell cordovan, owing to the dense structure of equine leather, is among the most resistant to daily wear.