A multi-part modular tool rotatable about a longitudinal tool axis (A), comprising: a machining head; a first holding element comprising a body elongated along the longitudinal axis (A) of the tool, in which a passage extends along the longitudinal axis (A) of the tool; a second holding element which can extend in the passage of the first holding element; wherein the machining head can be connected to the second holding element in such a way that the machining head is fixed firmly to the first holding element at least in the axial direction (A) and/or in the radial direction (R), and wherein the passage of the first holding element and the second holding element are adapted to one another such that during a connection process in which the machining head is connected to the second holding element, the second holding element is movable relative to the first holding element.