Patent ID: 8702356

Claim:
A fluted drill cutting head ( 14 ) comprising: two drilling portions ( 18 A, 18 B) facing axially opposite directions with respect to a head rotation axis (A), a plurality of cutting head coupling portions ( 19 ) and a plurality of head flute portions ( 42 ); wherein, in an axial view, the cutting head ( 14 ) has at least four see-through openings; each cutting head coupling portion ( 19 ) comprises a clamping recess ( 26 ), a cutting portion ( 22 ) and a non-cutting portion ( 24 ); the clamping recess ( 26 ) is located between the cutting portion ( 22 ) and the non-cutting portion ( 24 ); and a periphery of the clamping recess ( 26 ) is devoid of cutting edges.