You should note that setting up in 2005, Rolex commenced engraving the serial variety around the inner bezel (also called the rehaut) underneath the crystal at the 6 o’clock placement. Whilst the crystals around the 160xx era of Datejust watches remain constructed from acrylic, the sloped "pie pan" fashion dial https://www.watchesworld.com/a-history-of-watch-reference-numbers/