The TF file is made from a nickel-titanium wire that is heated, cooled, and twisted in a process developed by Kerr Endo, which gives it exceptional mechanical and physical properties. The TF file is the only file available on the market that has its mechanical properties optimized by the aforementioned twisting, heating, and cooling. It easily follows the path of the canal and provides possibilities for canal instrumentation that did not previously exist. It allows the use of a single nickel-titanium rotary instrument for the complete instrumentation of a high percentage of canals, regardless of their anatomy. Extremely flexible. Highly resistant to fracture.