The Rolex Datejust 31 reference 278240-0018 is a sophisticated mid-size timepiece that blends the brand’s classic aesthetic with modern horological engineering. This model features a 31mm Oyster case crafted from Oystersteel, a high-performance 904L alloy known for its exceptional corrosion resistance and brilliant finish. The watch is distinguished by its bright blue dial with a sunray finish and Roman numeral hour markers, providing a traditional yet striking appearance. It is equipped with a domed bezel and the iconic Jubilee bracelet, a supple five-piece link metal bracelet originally designed for the Datejust’s debut in 1945, which features a concealed folding Crownclasp.
At the heart of the timepiece is the manufacture caliber 2236, a self-winding mechanical movement that incorporates a patented Syloxi hairspring in silicon for superior resistance to magnetic fields and temperature variations. This COSC-certified movement offers a power reserve of approximately 55 hours and includes a date complication displayed at the 3 o’clock position, magnified by the signature Cyclops lens on the scratch-resistant sapphire crystal. The watch further ensures reliability with its Twinlock screw-down crown and Oyster architecture, providing water resistance up to 100 meters.
General reviews of the Datejust 31 reference 278240 highlight its versatility and refined proportions, making it an ideal choice for those who find the standard 36mm or 41mm models too large. Collectors and enthusiasts frequently praise the vibrancy of the blue sunray dial and the comfort provided by the Jubilee bracelet. While it is celebrated as a quintessential luxury everyday watch due to its durable Oystersteel construction and timeless design, some critics note that the mid-size market can be highly competitive, though Rolex’s Superlative Chronometer certification and five-year guarantee remain significant benchmarks for quality and precision in this segment.