A device for processing free-flowing input material is provided that includes a rotor rotating around a shaft within a housing, the rotor being fitted over its circumference with rotor tools. Stator tools, permanently fixed to the housing, are arranged, which are disposed opposite the rotor tools allowing a working gap and interact with the rotor tools to process the input material. The stator tools are held in a holder, forming a tool unit. The tool units are made self-supporting over the length of the rotor and end sections of the tool units are fixed removably in respective clamping devices.