Endodontic machine driven files, used in obturation of the root canal, can help ensure a precise and successful procedure. Some aspects to consider when purchasing an endodontic machine driven file are construction material, tip type, rake angle, tip variety and length, technique used and cross section. Most files are made of Nickel Titanium. The most popular tip type is a non-cutting tip. Most vendors offer tapered tips of a few different lengths for the perfect fit in any apical canal. A variety of techniques are used with endodontic machine driven files, a few are crown down, coronal and apical sequential. The cross-section of a file may be symmetrical, asymmetrical or triangular. Be sure to inquire about rake angle, as this may be the best indication for what type of endodontic machine driven file you are purchasing.