Internal Tool 64-4800 Chamfer Mills; Cutter Head Diameter (Fractional Inch): 3/16 ; Cutter Head Diameter (Decimal Inch): 0.1875 ; End Type: Single ; Shank Diameter (Decimal Inch): 0.1875 ; Shank Diameter (Inch): 3/16 ; Shank Length (Decimal Inch): 2.