1. Main application: widely used in making jacks, automobiles, motors, shocks, absorption machine structures and hydraulic pressure machines 2. Features: precision in sizes and good, granulation both for inside and outside face, smooth 3. Standard: GB3639-2000 and GB8713-88 4. Steel grade: 10#, 20#, 35#, 45#, 40Cr, 37Mn5, 20Cr 5. Outer diameter: 5.00mm-75.00mm (1/5"-3") 6. Thickness: 0.5mm-7.00mm (1/50"-1/4") 7. Length: as per customers' requirements