Abstract: A core chuck designed to lock the core of a roll of material winding and unwinding operations to a mandrel, which core chuck comprises a core and a tubiform cylindrical chuck body dimensioned to accommodate the core. Means are provided for fastening the chuck body onto the mandrel shaft. The chuck body defines on the surface opposite the core at least one recess disposed parallel to the rotating axis thereof which recess has a releasably terraced bottom step plate including at least one step ascending from a common center groove to each side of the recess. The top faces of the step and of the common center groove are substantially parallel to and spaced apart at different distances from the opposite smooth face of the core. At least one toothed roller is disposed in the recess with its axis parallel to the axis of the chuck body.