The date on the Datejust II is displayed in a window at 3 o'clock and changes instantaneously at midnight in a few thousandths of a second. The famous Cyclops lens on the crystal, invented by Rolex in 1953, magnifies the date two and a half times for easy reading. The Datejust II is also equipped with a mechanism allowing rapid adjustment of the date using the winding crown.
Waterproof to 100 meters(330 feet)
The Datejust II's Oyster case, guaranteed waterproof to a depth of 100 meters (330 feet), is a paragon of robustness and elegance. The characteristically shaped middle case , crafted from a solid block of material as well as the fluted case back which is screwed down. The winding crown, fitted with the patented Twinlock double waterproofness system, screws down securely against the case. The waterproof Oyster case provides the Datejust II's high-precision movement with optimal protection from water, dust, pressure and shocks.
The fluted bezel, a Rolex hallmark
The fluted bezel has been a hallmark of the Datejust since its launch, contribution unequivocally to its status as the most recognisable of watches, When the Oyster appeared in 1926, the fluting fulfilled a precise function: it served to screw the bezel down onto the case back with identical fluting. Over time, the fixing of the bezel is always crafted in 18ct gold and is a mark of distinction and prestige.
Parachrom Hairspring
The Datejust II equipped with a Perpetual rotor and the Rolex blue Parachrom hairspring pledges increased chronometric precision and reliability. This also allows for the Datejust II to be less prone to be affected by magnetic fields and is 10 times more resistant to shock than conventional hairsprings.