Product Name: Valve Seat Insert Mirrlees Blackstone ESL Model NO.: Mirrlees Blackstone ESL Material: X40crsimo10-2(DIN 1.4731) Material Standad: En10090: 1998<Valve Steels and Alloys for Interna> Hardness: 40-45HRC Outer Dia.: 3.5'(Nominal) Inner Dia.: 3.125' Height: 0.375'(Nominal) Seat Angle: 90 Degrees Intake Pressure Impulse: Supercharged Speed: Speed Piston Movement: Reciprocating Ignition Mode: Compression-Ignition Number of Cylinders: Multi-Cylinder Machines Cooling Cylinder: Water-Cooled Number of Strokes: Four-Stroke Cylinder Arrangement Form: L/V Trademark: TEQRUN Transport Package: Polywood Box Specification: GL, BV, CCS Origin: Nanjing China HS Code: 84099910 Product Description Description for Mirrlees Blackstone ESL Valve Seat Inserts:1. Material Grade:Standard: X40CrSiMo10-2(DIN 1.4731)Alternatives: X45CrSi9-3(DIN 1.4718)(comply with European Standard EN10090: 1998 Valve Steels and Alloys for Internal Combustion Engines)2. Stress released completely for dimensional stability.3. Seat face concentric to O/D within 0.02mm TIR.4. O/Droundness within 0.01mm.5. Seat face roundness within 0.01mm6. Proven Reliability By European and China Customers.