It is suitable for being installed on the pistol drill and bench drill, applicable for punching on these harder workpieces, such as stainless steel, carbon steel, aluminum plate, iron plate, etc.
Cobalt step drill bits are not made of pure cobalt, but rather a steel alloy with certain percent cobalt. The 5-percent alloy is known as M35 grade.
The cobalt increases the strength of the steel and makes it more heat-resistant, making them an ideal cutter for stainless steel, as well as softer materials like cast iron, titanium and other hard or abrasive metals.
The 5% blended cobalt also gives the bit a much longer life – an important point considering that step bits are difficult to sharpen.
Possibly, this will also be one of the most expensive single bits you own. Just keep in mind that you cover multiple sizes with each bit.