Case Size: 36mm Dial color: Silver Arabic Numbers Condition: Brand New Unwanted Gift Certificate: Yes June 2014 The Rolex Datejust was introduced in 1945 and appeared very similar to the Rolex Bubbleback. Original Rolex Datejust introduced in 1945This was also the same year of the 40 year anniversary of the Rolex company. The Datejust was introduced as the world's first pressure-proof, self-winding calendar wrist chronometer which automatically changed the date in its dial window. The key differences in the Datejust was the introduction of the date function at the three o’clock position and is slightly thicker than the Bubbleback to accommodate the date wheel, which contained alternating red and black date markers to distinguish between odd and even days.