Caliber Number / MovementMiyota 8215 (automatic with manual winding capacity)Power Reserve / AccuracyApproximately 42 hours ( 40 to -20 seconds per day)CrystalSapphire crystalLumiBriteLumibrite on hands, indexes and bezelCase & Band MaterialStainless steel case with synthetic rubber strapWater Resistance50mCase SizeThickness: 13.1 mmDiameter: 41.3 mmLength: 50.8 mmOther Specifications21 jewelsDate displayScrew case backScrew-down crownUnidirectional rotating bezel