Caliber 9F was developed to allow the creation of the ultimate quartz watch and is now widely recognized as one of the finest quartz calibers in the world. The suitability of this remarkable Grand Seiko quartz movement to the international traveler is enhanced by the addition of a GMT hand. The high precision (+/- 10 seconds a year) of Caliber 9F86 is not compromised when the time zone is changed as the watch continues to keep perfect time even when the crown is pulled out Exterior: Stainless steel Case back: Screw case back Glass Coating: Anti-reflective coating on inner surface LumiBrite: LumiBrite on hands and index(es) Case size: Diameter 39.0mm Lug-to-lug 45.9mm Thickness 12.3mm Band width: 19mm The perimeter of Band: 203mm Movement Caliber no.: 9F86 Instructions Accuracy: ±10 seconds per year Functions Water resistance: 20 bar Other details / Features: Screw-down crown 24-hour hand (dual time display function) Calendar-linked time difference adjustment function