A material reducing system comprising: a rotor that, in use, is rotated about a central axis , the rotor including a plurality of component mounting locations ; a plurality of components that are removably mountable at the component mounting locations and are configured for defining blank locations at an exterior of the rotor when mounted at the component mounting locations, and/or are configured for defining reducer locations at the exterior of the rotor when mounted at the component mounting locations, the components including: a) single-reducer hammers each including a reducing end and an opposite blank end , wherein when each of the single-reducer hammers is mounted to the rotor at one of the component mounting locations, the reducing end defines one of the reducer locations at the exterior of the rotor and the blank end defines one of the blank locations at the exterior of the rotor; or b) separate reducing components and blank components that are interchangeably mountable at the component mounting locations, the reducing components each defining one of the reducer locations at the exterior of the rotor when mounted at one of the component mounting locations, and the blank components each defining one of the blank locations at the exterior of the rotor when mounted at one of the component mounting locations. a rotor that, in use, is rotated about a central axis , the rotor including a plurality of component mounting locations ; a plurality of components that are removably mountable at the component mounting locations and are configured for defining blank locations at an exterior of the rotor when mounted at the component mounting locations, and/or are configured for defining reducer locations at the exterior of the rotor when mounted at the component mounting locations, the components including: a) single-reducer hammers each including a reducing end and an opposite blank end , wherein when each of the single-reducer hammers is mounted to the rotor at one of the component mounting locations, the reducing end defines one of the reducer locations at the exterior of the rotor and the blank end defines one of the blank locations at the exterior of the rotor; or b) separate reducing components and blank components that are interchangeably mountable at the component mounting locations, the reducing components each defining one of the reducer locations at the exterior of the rotor when mounted at one of the component mounting locations, and the blank components each defining one of the blank locations at the exterior of the rotor when mounted at one of the component mounting locations. a) single-reducer hammers each including a reducing end and an opposite blank end , wherein when each of the single-reducer hammers is mounted to the rotor at one of the component mounting locations, the reducing end defines one of the reducer locations at the exterior of the rotor and the blank end defines one of the blank locations at the exterior of the rotor; or b) separate reducing components and blank components that are interchangeably mountable at the component mounting locations, the reducing components each defining one of the reducer locations at the exterior of the rotor when mounted at one of the component mounting locations, and the blank components each defining one of the blank locations at the exterior of the rotor when mounted at one of the component mounting locations. <EOS>