This disposable plastic 13 Point Snap Knife make use of a Snap-off old blade system. Whenever the blade gets dull, extend the Knife then simply "Snap" the dull blade off and a new edge is ready for you to get back to work. No fumbling trying to place in a new blade that you had to look all over for. This 13 Point Snap Knife includes three full replacement blades or 39 points per Knife.