Materials: Alloy-steel of high quality 1) 38CrMoAIA(JIS SACM 645) 2) 9Cr18MoV Nitrided hardness: HV900-1000 Nitrided Case Depth: 0.5mm-0.6mm Alloy hardness: HRC50-65 Alloy depth: 0.8mm-2.0mm Advanced nitriding process Corrosion & Abrasion resistance bimetal spraying process. Wooden case.