CNC precision machined, nickel plated and made of high quality steel. These cutters are heat treated and have sharp edges engineered for accurate cutting and long life. Always buy a set of dies made exactly for your material thickness. If you have a variety of material thickness, you will need more than one set of dies. Trying to cover very thin and very thick material with the same set of dies will result in poor quality buttons. You need a set of die with cutter for each button size. Wooden dowel used to push the material into the die is also included.