Full Oystersteel with a smooth bezel and black dial — the Lady-Datejust 178240 takes the most pared-back approach possible within the collection. There is no gold, no fluting, no gemstones; just clean stainless steel architecture with a dark dial that maximises contrast and legibility. At 31mm, it is the mid-size option for buyers who want a Datejust with a sportier personality and the versatility of a monochrome steel watch.
Key Specifications
| Specification | Detail |
|---|---|
| Reference | 178240 |
| Case Size | 31mm |
| Case Material | Oystersteel |
| Bezel | Smooth domed, Oystersteel |
| Dial | Black |
| Crystal | Sapphire with Cyclops lens |
| Movement | Automatic with date |
| Water Resistance | 30m |
| Bracelet | Oyster, three-piece links |
| Clasp | Folding Oysterclasp |
| Functions | Hours, minutes, seconds, date |
The 178240 Black Dial Up Close
The black dial absorbs ambient light, creating maximum contrast against the applied stick markers and luminescent hands. This is a high-legibility configuration: white luminescent fill on the indices and hands stands out sharply against the dark surface, and the Cyclops-magnified date at three o’clock is readable at a glance. No sunburst effect here — the finish is a clean, flat black.
The smooth steel bezel reinforces the utilitarian aesthetic, sitting flush and unadorned above the dark dial. The Oyster bracelet in full Oystersteel completes a cohesive monochrome look from case to clasp. See all steel Lady-Datejust options in the Lady-Datejust collection.
Movement Options: Swiss vs Japanese
Choose from two automatic movement tiers:
- Swiss automatic — smooth high-beat sweep, extended power reserve, and architecture following the genuine Lady-Datejust caliber. Best for collectors prioritising mechanical refinement.
- Japanese automatic — reliable Miyota-based caliber with globally accessible servicing and proven daily accuracy. A practical choice for everyday wear.
Both feature quickset date and hacking seconds for precise synchronisation.
Shipping, Warranty and Returns
Every order ships with discreet packaging and full tracking. Delivery times vary by destination — see our shipping policy for detailed timeframes and methods. This watch is covered by our standard movement warranty. If your purchase does not meet expectations, review our return and exchange policy for available options.








1 review for Replica Rolex Lady-Datejust 178240 Mid-Size 31mm Black Dial