2Jewellery Men's Automatic Watch, Multifunctional dial design, artificial sapphire glass. Movement: CAL.3H31 Model: 1919 Drive: single-spring drive Power reserve: 42 (hours) Vibration frequency: 28800 (times/hour) Winding method: manual winding Case diameter: 45-30mm Case Thickness: 11.9mm Strap width: 26*20mm Case material: stainless steel Strap Material: Rubber Waterproof depth: 5ATM Watch mirror material: Synthetic sapphire crystal Buckle style: Butterfly double snap Crown: Straight