Seiko Prospex x Automatic ft. 1968 Heritage Modern Re-Interpretation aka Marinemaster GMT Men Diver Round 300m Water Resistant Watch HBC002J1 HBC002 HBC-002 HBC-002J1 Conquer land and sea with the Seiko Prospex HBC001, a 1968 Heritage GMT diver featuring a black dial and ceramic bezel. Powered by the automatic Caliber 6R54 with a 72-hour reserve, it boasts 300m water resistance, a new tool‑free micro‑adjust clasp, and Lumibrite for low‑light visibility. Caliber Number / Movement 6R54 (automatic with manual winding capacity) Power Reserve / Accuracy Approximately 72 hours (+25 to -15 seconds per day) Crystal Sapphire crystal (anti-reflective coating) Luminous LumiBrite on hands, indexes and bezel Case / Band Material Stainless steel case, ceramic bezel insert with stainless steel band (three-fold clasp with secure lock, push-button release with slide extender) Water Resistance 300m / 1,000ft diver Case Size Thickness: 13.3 mm Diameter: 42.0 mm Length: 48.6 mm Lug width: 20.0 mm Other Specifications Seiko Prospex x Automatic ft. 1968 Heritage Modern Re-Interpretation aka Marinemaster GMT Made in Japan Magnetic resistance (4,800 A/m) Unidirectional rotating bezel Screw-down crown Screw case back 24 jewels Date and 24-hour (GMT dual time) display Stop second hand function (hacking mechanism) Regular timekeeping (analog display)