... .material : AISI1020 Material ASTM/AISI 1020Feature:High hardness with a soft core giving resistance to shock load & excellent resistance to surface ... and allow rotating parts, for example: castors, conveyors, roller skates, drawer slides, seat slides, bicycles, etc.CertificationISO 9002: 2000OriginalShandong province , China AISI 1020 ...