Movement type: Seiko NH35 automatic mechanical movement Movement features: 3 hands/calendar frequency 21600 times per hour (3Hz) stop-second device two-way automatic winding 24 stone 41 hours of energy storage. Case material: 316L stainless steel Bottom cover type: screw-in bottom cover Case diameter: 42mm (without crown) Case length: 52.5mm (total length from top to bottom) Case thickness: 13.5mm (including table mirror and bottom cover) Case Lugs position: 20mm Watch mirror material: synthetic sapphire Crown type: screw-in Bezel material: ceramic ring Bezel Luminous: Swiss C3 super luminous powder glowing green Waterproof level: 200 meters waterproof / diving [can wash hands swim dive meet all daily waterproof use]