Can be used for painting expansion work with an impact screwdriver. The 0.25 inch (6.35 mm) hex shaft allows you to work with an impact driver. Total length: 21.7 inches (550 mm) Shaft diameter: 0.25 inch (6.35 mm) hexagonal shaft Compatible blades: H blades, HL blades, HS blades, HR blades, S blades. Material: ● Shaft: S45C