Rolex
Datejust 31 178240-0022— lug 16mm

The Rolex Datejust 31 ref. 178240-0022 has a lug width of 16mm. This measurement is specific to the Datejust 31 line and requires straps designed for this attachment, as the Oyster lug profile has a slightly tapered inner geometry that is not compatible with all generic 16mm straps.

For the steel Datejust 31 with a smooth bezel, a vegetable-tanned alligator strap is the most coherent choice given the case's formal character. Alternatively, box-grain calf leather suits daily wear, while high-grade vulcanised rubber offers water resistance without compromising aesthetics. All materials should be paired with a 16mm steel buckle or deployant clasp to maintain visual harmony with the Oystersteel case.

To replace the strap on the Datejust 31, use a fine-tipped spring bar tool or a dedicated Rolex spring bar screwdriver. The 16mm spring bars are released by applying gentle inward pressure towards the case within the lug slot. Always work on a soft surface to avoid scratching the case, and ensure that replacement spring bars match the correct diameter — typically 1.5mm for this format.

Yes, high-quality aftermarket straps are available specifically designed for the 16mm lug width of the Datejust 31. It is essential to choose manufacturers who respect the Oyster lug geometry, with appropriately curved and tapered ends. Milano Straps offers a curated selection of 16mm straps tested for compatibility with this reference, available in various materials and finishes.

The lifespan of a leather strap depends on the material, care routine, and frequency of use. A quality vegetable-tanned alligator strap, kept away from water and excessive perspiration and treated periodically with a specific leather conditioner, can last between three and seven years while retaining structural integrity and a refined appearance. Box-grain calf leather has a similar lifespan but develops patina more readily. Milano Straps offers an 18-month guarantee covering manufacturing defects.