1. Color: Plain, black, zinc blue, zinc yellow 2.Material: Steel, stainless steel 3.We have the certificate:Iso 9001:2000 Place of OriginShang Hai China(mainland)MaterialCarbon steel & stainless steelSizeAll frequently-used size, produce as your requirement is okStandardDIN,BSW,ANSI,ISO & non-standard productsSurfacePlain, Y.Z.P., Black, Z.P.QualityBe affordable but of very high qualityPaymentTT ...