Seiko Diver 6105-8110

Seiko stainless steel automatic calendar centre seconds diver's wristwatch, signed Seiko, 150m Proof, ref: 6105-8110, so called by collectors as the 'Captain Willard', circa 1970 , lever movement, black dial with luminous hour markers, date aperture, bi-directional 60-minute bezel, crown at 4, tonneau shaped case with a screw back numbered 230657 41mm wide, on plastic strap