From Seiko, the Men's Prospex Special Edition Manta Ray Automatic Diver Blue Silicone Strap Watch features:  Prospex Save the Ocean Deep blue silicone strap Buckle closure Stainless steel case Screwdown crown and special edition caseback "Manta Ray" themed gradient blue dial with stamped wave pattern Black ceramic uni-directional rotating elapsed timing bezel Sapphire crystal with anti-reflective coating on the inner surface Automatic diver Manual and automatic winding capabilities Approx. 21,600 vibrations per hour Power reserve approx. 41 hours 24 jewels Magnified day/date calendar LumiBrite hands and markers Case diameter approx. 45.0mm Water Resistance: 200 meters (660 feet) Diver's watch Follows ISO standards and is suitable for scuba diving Imported.