Movement type: seiko NH35 automatic mechanical movement Movement characteristics: 3 hands / calendar, frequency 21,600 times per hour (3Hz), stop seconds device, two-way automatic winding, 24 stones, 41 hours of energy storage. Case material: CUSN8 bronze imported from Germany Case technology: sand Bottom cover material: 316L stainless steel Bottom cover type: screw-in bottom cover Case diameter: 44mm (without bar) Case length: 48mm (total length from top to bottom) Case thickness: 12mm (including table mirror and bottom cover) Case ear position: 20mm (the link between case and strap) Watch length: 250mm (total length of watch / circumference) Watch mirror material: synthetic sapphire Watch mirror type: plane + calendar magnifying glass Watch mirror coating: anti-glare blue coating Bar head type: screw-in screw lock bar Bezel features: 120 teeth ring one-way rotation Waterproof level: 200 meters waterproof / diving [can wash hands, swim, dive, to meet all daily waterproof use]