Cutting Diameter: 7/16"; Shank Diameter: 3/8"; Flute Length: 1"; Overall Length: 2-11/16" 8% cobalt ensures high edge hardness at elevated temperature levels. Higher speeds and increased feeds.; Great abrasive resistance. Longer tool life than ordinary high-speed steel. 4 Flutes; Single End; Center Cutting; 30-degree Helix Angle; Weldon shank Right hand (clockwise rotation) cutting direction Have standard lengths and sized to offer good rigidity Spiral flute design offers a fast and smoother cutting action