Citizen Men's Watch PROMASTER MARINE Series Mechanical Diver 200m Urethane Band NB6021-17EProduct Highlights p> Inspired by the legendary "Fujitsubo Diver," a mechanical diver's watch beloved for its resilience even when covered in barnacles after being lost at sea. The new model, "Challenge Diver," retains the iconic design while updating specifications and materials. The rounded case design visible from the side view, the concave bezel, and the nostalgic finish of the case width, mirror, and hairline all evoke a sense of familiarity.