Due to their unique design, Autio Style Knives are designed to be used only on Autio machines. These knives fit together with a breaker plate to perform a double cutting action. This combination is excellent for heavy duty break grinding operations (i.e. frozen, bones, seafood shells, etc.). 8-5/8" grinders used 3-arm knives while 11" grinders use either 4 or 6-arm knives. All Autio knives include insert blades. Larger center drives are also available for Autio pump grinders.