Variable tooth unique variable tooth geometry for consistent cutting ability in a wide range of materials Manufactured to strict Alpha specifications to suit demainding Australian conditions 8% cobalt Bi-metal gives ultimate performance and superior welding technology prevents tooth strippage 38mm cutting depth Recommended Speeds Mild Steel 75 Cast Iron 50 Tool Steel Stainless 35 Brass 92 Aluminium 95 Wood 800 Recommended for use with large arbor or large quick release arbor.