CMT 317.400.11 Hinge Boring Bit, 40mm (1-37/64-Inch) Diameter, 10x26mm Shank, Right-Hand Rotation 57.5mm (2-17/64-Inch) Overall Length. Premium quality super-strength steel body and spiral portion with center point 2 precision ground cutting edges, 2 spiral flutes, 2 negatively ground spurs Ideal for hinges. Used on boring machines equipped with chucks or adaptors Used for drilling accurate and clean-cut blind holes in wood, wood composites, laminated materials