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 55 Cast Iron 35 Tool Steel Stainless 25 Brass 75 Aluminium 75 Wood 800 Recommended for use with large arbor or large quick release arbor.