Countersink Size : 1/4
Decimal Equivalent:  1.2500" 
Shank Size: 3/4" 
Overall Length:  3-3/8"
Number of Flutes: 6
Direction of Cut: Right Hand 
Geometry/Tool Specs: 60° 
Material: High Speed Steel 

Self Centering. Designed for fast shearing and chatterless cuts. They can produce a fine finish operating at higher speeds.