31. 31Y Omega. A stainless steel manual wind chronograph wristwatch Omega. Chronographe bracelet en acier mouvement mécanique Model: Speedmaster Reference: 311.33.42.30.01.002 Date: Purchased 4th May 2015 Movement: 18-jewel Cal.1863 manual wind, No.87282523 Dial: Black, white baton hour markers, white outer second and minute divisions, sunken subsidiary dials at 3, 6 and 9 for seconds, 30 minute and 12 hour recording, white pointed baton hands with luminous inserts, centre chronograph hand Case: Brushed and polished tonneau form, exhibition screw down back, twisted lugs, shouldered crown flanked by twin pushers, black tachymetre insert to bezel Strap/Bracelet: Omega black alligator leather Buckle/Clasp: Signed folding clasp Signed: Case, dial & movement Size: 42mm Accompaniments: Omega box, outer card, International Guarantee card, two spare black NATO straps, tool, spare parts, Original receipt dated 04/05/2015, Pictograms card