Key Steel / Machine Key / Square Key BarImperial or Metric sizes.Length: 300mm, 305mm, 500mm, 1000mm, 2000mm, 3000mm, etc. Material: Carbon steel C1035, C1045, A3.Stainless steel ANSI 304, 316.Surface Finish: Plain, Zinc Plating, Black. Size, thickness, style or other specifications can be designed according to your demand.