godhand quick attachable drill bit set 5pcsHexagonal shaft drill blades specialized for model building! Drills holes without worries about idling. Hexagonal shaft with a diameter of 4 mm and 5 drill blades with diameters of 0. 5 mm, 0. 6 mm, 0. 7 mm, 0. 8 mm, and 0. 9 mm. Hexagonal shaft meshes firmly with the connection part to pevent idling. Compared to general drill blades, shorter overall length and closer distance to the target enable easier targeting and handling. Obtuse cutting edge of