... , ballscrew, linear bushing,support rail unit and Linear Bearing Unit.And for Linear shaft has following features,Meteria:GCR15Hardness:HRC62+-2Accuracy:G6Roughness ... , WCS25, WCS30, WCS35, WCS40, WCS50, WCS60, WCS80. Chrome plated Linear Shaft Diameter 3mm ,linear round bar,linear motion bearing Shaft ,Bearing Steel linear ball ...