Burrs – are normally two pieces of serrated hardened steel or ceramic that mill coffee. They’re often housed in espresso grinders with direct drive or belt driven motors to make the burrs spin. Burrs are not to be confused with blades. Grinder burrs cut as opposed to crushing beans. They often come in two styles Flat (Disc Shaped) or Conical (Cone shaped). Burrs are more precise and grind hard coffee beans into a uniform ground coffee.
See Flat burrs, Conical Burrs and Coated Burrs
Shop Coffee Grinder Burrs on Bella Barista website.