Internal Tool 64-1426 Chamfer Mills; Cutter Head Diameter (Fractional Inch): 5/8 ; Cutter Head Diameter (Decimal Inch): 0.6250 ; End Type: Double ; Shank Diameter (Decimal Inch): 0.6250 ; Shank Diameter (Inch): 5/8 ; Shank Length (Decimal Inch): 2.88