precision seamless steel pipe, used in motorcycle industry, cylinder, shock absorber, jack, hydraulic pressure machine precision seamless tube Specification details: 1. Main use: widely used in ... outer surface 3. Standard: GB3639-2000 and GB8713-88 4. Steel grade: 10#, 20#, 35#, 45#, 40Cr, 37Mn5, 20Cr5. Outer ... . Packing:In bundle with strip or in carton box Shock Absorber seamless steel tube