Promotion steel key ring 1.Material: steel, stainless steel 2.Outter diemeter:2~5CM 3.Wire die:1.0~3.0mm Promotion Steel key ringFeatures: 1) Wire Diameter: 1.0~ 3.0mm 2) Type: Key ring. 3) Main material: carbon spring steel, steel, stainless steel, alloy5) Surface treatment: Zinc plating, powdering coat, nickel plating etc. or customized coating is available.6) Good hardness, Long service-life, ...