Material: Brass.Wheel Brush Diameter: 5mm (0.20" approx).Shank Length: 40mm (1.57" approx).Shank Diameter：3.17mm (0.12" approx).This Pencil Polishing Brush is great to use for polishing and finishing step.Used widely in aerospace， plant maintenance， foundry， automotive， metal fabrication and shipyards.Package List:10PCS Brass Pencil Brushes