Grand Seiko Watch Spring Drive SBGA001J. Seikos Spring Drive movement is something unique and made entirely in house. This watch is equipped with 9R86 calibre, which utilizes elegantly the Spring Drive technology. The movement comes with 30 bearing jewels and features a 72 hour power reserve. It is protected from magnetic influences and water penetration. A date window is positioned conveniently at the 3 o clock mark. The dial is also equipped with a power reserve indicator. Additional functionalities include a screw crown, a transparent case back and scratch resistant sapphire crystal glass with anti reflective coating.