Grand Seiko Watch Spring Drive GMTThe Seiko SBGE001 Spring Drive GMT timepiece is a relatively big one, it comes with a case diameter of approximately 44 millimetres. It has a 9R66 calibre that utilizes elegantly Seikos Spring Drive technology and features 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. This watch is equipped with a dual time display function. A date window is positioned conveniently at the 4 o clock mark. Hands and indices are luminous for improved visibility in even the toughest of conditions. One of the most specific Spring Drive GMT watch functions is the uni directional elapsed time bezel. Additional functionalities include a screw case back, screw crown and scratch resistant sapphire crystal glass with anti reflective coating.