a device for mounting a roll of material that includes a fiber core around which the material is placed . the device includes a lightweight , polymeric collett that is inserted into the fiber core . the polymeric collett has a plurality of individual segments that expand radially with respect to a central axis of the roll of material . each of the plurality of individual segments includes an inner wall and an outer wall . the inner walls of the plurality of individual segments define a cavity . the outer walls engage an interior surface of the fiber core . an arbor engages the inner walls of the plurality of individual segments and forces them outwardly to place the outer walls into tight , frictional engagement with the interior surface of the fiber core .