... or samples;5.grade:4.8,6.8,false 8.0 ,true 8.0,8.8 and etc;6.material:carbon steel(incude A3#,34#,45#,etc,),brass;stainless ... plating,blue zinc plating,environmental galvanizing,hot-dig-galvanizing,etc;8.manufacture method:be made by cold-forming & hot-forming;9 ...