Dormer A1174.9 HSS-E Straight Shank Stub Drill Bits 4.90mm (Box of 10) The Dormer A1174.9 and its heavy duty design provides increased strength for drilling difficult materials. They have a head diameter of 4.90mm and are sold in a box of 10. Features: 135 degree split point provides self centering, low thrust and easier penetration Bronze finish identifies Cobalt based substrate and reduces built-up-edge For use on machines or hand held applications Specification: DIN1897 Head Diameter: 4.90mm Cutting Length: 26mm Overall Length: 62mm