Abstract: The invention comprises a roller having circumferentially extending slits through which extend blades having an outerwardly facing cutting surface. The blades are detachably mounted from a retractable bar whereby the cutting surface extends beyond the roller or is retracted below the outer surface of the roller. A pivoted protective cover assembly fits adjacent to the slitted rollers and retracts the blades when the cover is lifted away from the slitted roller. Means are provided to position the slitted roller laterally with respect to the film to be slitted.