Pre-owned, barely used Constellation purchased a few years ago from an authorized Omega dealer, has serial number on case and movement. Check wrist size before ordering as bracelet is short, the original owner had a couple of links removed and did not keep them. Having said that a link could be ordered and would not be very expensive. This model has a transparent sapphire back which allows you to see the 27 jewel movement which is adjusted to 5 positions and temperature. This watch has the reference number 15035100 and has a white dial, the watch number is 80691345, it was purchased at Chadwick Jewellers in Hawaii in 2004 with a black dial and the dial was changed for a white one by an Omega dealer in Toronto. The watch comes with the international warranty card, a chronometer certificate and a third card called pictograms that states the movement calibre no 2500. Watch is in very good condition with minor scuff marks and is in excellent working condition. Measures 38 across (not including crown or crown guards) and fits a 18.5 cm (7 1/4 inch) wrist.