Product ParametersMovement: CAL.3H31Movement model: 1919Drive: single-spring drivePower reserve: 42(hours)Vibration frequency: 28800 (times)Winding method: Manual windingCase Diameter: 45-30mmCase Thickness: 11.9mmStrap width: 26x 20mmCase material: 316 stainless steelStrap Material: RubberWaterproof depth: 50 meters life waterproofMirror: Artificial sapphireBuckle: Double Butterfly SnapCrown: straight