Case Material : Stainless steel Glass Material : Dual-curved sapphire crystal Glass Coating : Anti-reflective coating on inner surface Case size : Diameter 43.5mm Lug-to-lug 51.2mm Thickness 16.1mm The perimeter of Band : 201mm Clasp type : Three-fold clasp with push button release
Caliber no. : 9R86 Movement Type : Spring Drive Power reserve : Approx. 72 hours(3 days) Accuracy : ±1 second per day / ±15 seconds per month (average)
Water resistance : 10 bar Magnetic resistance : Equipped Weight : 187.0 g Other details / Features :
- ・24-hour hand (dual time display function)
- ・50 jewels
- ・Calendar-linked time difference adjustment function
- ・Chronograph with 30 minutes & 12 hours
- ・Power reserve display
- ・Screw case back
- ・Screw-down crown
- ・See-through case back
- ・Stop seconds hand function
The first ever Grand Seiko chronograph, this model is powered by a Grand Seiko’s unique Spring Drive caliber, which combines the motive force of a mainspring with the high precision of a quartz watch.
The Spring Drive mechanism allows the watch to maintain precise timekeeping while also incorporating accurate chronograph capabilities, all with a maximum 72-hour (3-day) power reserve.
Grand Seiko's original glide motion is also featured in the chronograph's blue steel second hand.
The chronograph utilizes a Ready/Start button with a half-press shutter, to ensure the most precise possible operation, the chronograph start an stop buttons have a ‘ready’ stage so that the chronograph is armed by pressing the button half way.