Heavy-duty utility knife with an auto-lock mechanism delivers extra productivity and savings with the ease and speed of snapping off a blade segment to renew its cutting edge. Simply slide the blade disposal container off the knife, insert the dull blade into the end of the container and snap it off. The old blade disappears into the container, and a sharp new blade is ready for use. Utility knife is perfect for cutting tape, shrink-wrap, wallpaper, film, cardboard, caulking and more.