Citizen Mechanical Watch Automatic Citizen Collection Mechanical CITIZEN COLLECTION Men's Watch NH9111-11B Accuracy -20 to +40 seconds/day Case: Stainless steel Width: 40.0mm, Thickness: 12.9mm 10 ATM water resistance Duration: Approximately 40 hours (when fully wound) Glass: Spherical sapphire glass Band: Calf leather Buckle type Design: Partial skeleton, see-through back Functions: Seconds hand stop function Frequency: 21,600 beats/hour Number of jewels: 21 Accessories are not included; only the watch itself will be shipped. *Purchased from this site. After purchasing, I bought an aftermarket strap, but I rarely used it. Even the CITIZEN original strap is in good condition and I think it can still be used for a long time. This time, I will specially include the aftermarket strap as well.