Abstract: A device for comminuting media materials that store sensitive information. The device is a rotating mill core with removable flat edged blades, a set of stacked bed knives and a screen. The mill core rotates in close proximity to the bed knives to shear the material being fed, and in close proximity to the screen in order to grate the material. A flywheel is attached to the mill core in order to conserve rotational energy and improve the efficiency of the device. A knurled roller is installed in the device that feeds the material into the knife mill as well as holds the material steady during the initial shear. Vacuum ports facilitate cleanup.