Main use: widely used in making autobicycle, automobiles Specification details: 1. Main use: widely used in making jacks, automobiles, motors, shock absorber, absorption machine structures and hydraulic pressure machines 2. Features: precision in sizes and good roughness on inner and outer surface 3. Standard: GB3639-2000 and GB8713-88 4. Steel grade: 10#, 20#, 35#, 45#, 40Cr, 37Mn5, 20Cr 5. ...