Exterior: Stainless steel Case back: See-through & Screw case back Glass Material: Box shaped sapphire crystal Glass Coating: Anti-reflective coating on inner surface Case size: Diameter 40.0mm Lug-to-lug 47.0mm Thickness 12.9mm Band width: 21mm Clasp type: Three-fold clasp with push button release The perimeter of Band: 190mm Movement Caliber no.: 9S85 Instructions Movement Type: Automatic with manual winding Power reserve: Approx. 55 hours Mean daily rate: +5 to -3 seconds per day Mean daily rate is a mean value of daily rates in a condition where the movement before assembly in a case is measured in six positions in a fixed manner under artificially controlled environment for 12 days. Normal usage accuracy: +8 to -1 seconds per day Functions Water resistance: 10 bar Magnetic resistance: 4,800 A/m Weight: 153 g Other details / Features: Screw-down crown 37 jewels