Seiko Prospex Mens Black Ion Leather Band Black Quartz Dial Watch - SSG015. PROSPEX COLLECTION: The challenge of sports has inspired Seiko to create new technologies new materials new functions and new display systems to serve the needs of true sports enthusiasts worldwide. With aviation watches Seiko invented the trigonometric slide rule that allows pilots to make complex calculations in flight. Ever since the challenge of sports has inspired Seiko to create new technologies to serve the needs of true sports enthusiasts worldwide. Radio Controlled World Time Functions in 25 Time Zones Glass Case Back Hardlex Crystal with Anti-Reflective Coating Three (3) Year Limited ManufacturerÕs Warranty Water resistant depth: 100 Meters