Grand Seiko Heritage

Spring Drive GMT with a classic appearance and innovative heart

This model features a Spring Drive, the third movement mechanism, combining the motive force of a mainspring found in mechanical watches with the high precision of a quartz watch, as well as a GMT indicator, all incorporated into a classic design.

The motion of the second hand, smoothly gliding over the black dial, is enabled by the watch's exclusive sweeping mechanism. This motion is different from that of either a mechanical watch or a quartz watch. By placing a simple 24-hour scale inside the classical rail track scale, we designed the watch to maintain a formal style with an additional feature of a GMT indicator.

Exterior
Case Material : Stainless steel
Glass Material : Box shaped sapphire crystal
Glass Coating : Anti-reflective coating on inner surface
Case size : Diameter 40.2mm × Thickness 14mm
Band Material : Crocodile leather
The perimeter of Band : 187mm
Clasp type : Three-fold clasp with push button release

Movement
Caliber no. : 9R66 Instructions
Movement Type : Spring Drive
Power reserve : Approx. 72 hours(3 days)
Accuracy : ±1 second per day / ±15 seconds per month (average)

Functions
Water resistance : 10 bar
Magnetic resistance : Equipped
Weight : 93.0 g
Other details / Features :
・24-hour hand (dual time display function)
・30 jewels
・Calendar-linked time difference adjustment function
・Case back with 6 screws
・Case back with lion emblem
・Date display
・Power reserve display
・See-through case back
・Stop second hand function