SEIKO Prospex Marinemaster 1968 Heritage Diver's Watch SLA077J1Collection: Prospex Marinemaster 1968 Heritage Diver's Watch Crystal: Dual curved sapphire crystal with anti reflective coating on inner surface Movement: Automatic with manual winding (Caliber 8L35); approx. 50 hour power reserve; 26 jewels; accuracy +15 to 10 sec per day; 28,800 vph; stop second hand; date display Water resistance: 300 m 1000 ft diver's Case material: Stainless steel Case size: Diameter 42. 6 mm; Thickness 13. 4 mm; Lug to lug 49. 3