Lutz heavy-duty retractable utility knives are designed to be reliable. Die cast from zinc for optimum strength and durability, they are built to last a lifetime. The Lutz #82 knife is a heavy duty, industrial quality retractable utility knife. The specially built zinc retractor allows for smooth operation in three cutting positions. It fits in your hand comfortably and provides you with a safer, more reliable tool. It has 3 heavy duty replacement blades stored inside the knife.