The Rolex Datejust 31 reference 278240-0017 is a contemporary luxury timepiece featuring a 31mm case crafted entirely from Rolex’s proprietary Oystersteel. This model is characterized by its bright blue sunray dial, which is adorned with polished 18k white gold Roman numeral hour markers and a matching handset. The watch utilizes a smooth, domed bezel and is integrated with a three-piece link Oyster bracelet. This construction includes an Oysterclasp and the Easylink comfort extension system, allowing for a 5mm adjustment in bracelet length for improved wearability.
Technically, the timepiece is powered by the manufacture caliber 2236, a self-winding mechanical movement that is COSC-certified as a Superlative Chronometer. This movement features a patented Syloxi hairspring in silicon, providing high resistance to magnetic fields and temperature variations. It offers a power reserve of approximately 55 hours and maintains a precision of -2/+2 seconds per day. The watch includes a date complication with a rapid-setting function, displayed under a scratch-resistant sapphire crystal equipped with a Cyclops magnification lens. Its Oyster case, featuring a screw-down Twinlock crown, ensures a water resistance of 100 meters.
General reviews of the Datejust 31 emphasize its role as a versatile mid-size option that balances elegance with a robust, sporty build. It is frequently noted for its clean, minimalist aesthetic compared to models with fluted bezels or Jubilee bracelets. The sunray blue dial is often praised for its depth and light-reflecting properties, though some critics mention that the Roman numeral dials lack luminescence, which may affect legibility in low-light conditions. Overall, it is regarded as a durable and reliable luxury dress watch suitable for both daily wear and formal occasions.