Features: 316L Stainless Steel Case Black Silicone Strap Automatic Movement Caliber: Seiko NH36 Sapphire Crystal With Anti-Reflective Coating Black Dial With Logo 'RATIO' Analog Display Stainless Steel Bezel With Black Aluminium Inlay Helium Safe Valve Power Reserve Upto 40 Hours Luminous Hands And Markers Day And Date Display Stainless Steel Screw Down Crown Stainless Steel Solid Screwed Case Back Engraved Case Back With Image Of A Free Diver Stainless Steel Buckle Clasp 1000M Water Resistance Approximate Case Diameter (Without Crown): 46.00 mm Approximate Case Diameter (With Crown): 50.00 mm Approximate Case Thickness: 15.40 mm Approximate Lug Width: 24.00 mm