... , 37Mn5, 20Cr; Standard: DIN 2391, GB/T 3639; Cold Rolled Precision Seamless Steel PipeSteel grade: 10#, 20#, 35#, 45#, 40Cr, 37Mn5, 20Cr;Standard ... "-0.8661"); Application: The products are used for jack, structural tube of automobile, absorber, and hydraulic pressure facility etc