No.002
Professional 600m
diver's watch
(Mechanical movement : 6159)

Commercialization: in 1975

Feature:

The professional diver's watch model of 600m saturation diving specification which used Ti (titanium) for the first time in the world for the case material of a diver's watch; the high performance self-winding movement was used (with hand-winding mechanism) that is the caliber of the ten beats same as [61] GS (Grand SEIKO). There are 20 world's first technologies in this case; such as one-piece case structure, L shaped glass gasket structure, glass screw ring fixing structure, twin side shield crown structure, special elastic strap made from polyurethane rubber.