Make sure you Observe that starting in 2005, Rolex commenced engraving the serial range about the inner bezel (also known as the rehaut) underneath the crystal on the 6 o’clock place. Whilst the crystals about the 160xx technology of Datejust watches remain produced from acrylic, the sloped "pie pan" model https://www.watchesworld.com/a-history-of-watch-reference-numbers/