Rubber pined screw and barrel specification: 75mm~+200mm Rubber cold or hot-feed screw and barrel specification: 30mm~+250 mm Nitrided Hardness: HV900-1000 Nitrided case depth: 0.45mm-0.7mm Alloy hardness: HRC50-65 Alloy Depth: 0.8mm-2.0mm Materials: Quality 38CrMoAlA Advanced nitriding process Corrosion&Abrasion resistance bimetal spraying process