Grand Seiko Watch Spring Drive GMTGrand Seiko SBGE005 is a GMT Spring drive timepiece that makes use of Seikos unique technology. The timepiece is equipped with 9R66 automatic calibre that has 30 bearing jewels. The movement comes with a 72 hour power reserve. It is protected from water penetration and magnetic influences. A power reserve indicator is available for the convenience of the wearer. Grand Seiko SBGE005 features a 24 hour GMT display. A date window is positioned at the 3 o clock mark. Additional functionalities include a blue steel 24 hour hand, a screw crown, see through case back and scratch resistant sapphire crystal glass with anti reflective coating.