These files utilize the reciprocating technique for the preparation of root canals with a single instrument. In the reciprocating technique, the instrument is first driven in a cutting direction and then a reverse rotation occurs to release the instrument. A 360° rotation is completed with several reciprocating movements. The angle in the cutting direction is greater than the angle in the reverse direction, allowing the instrument to continuously advance towards the apex. The angles of the reciprocating technique are precise and specific to the design of the RECIPROC® instrument and VDW endodontic motors. They have been designed to be below the angle adjustments, where the elastic limit of the instrument would be reached, thereby minimizing the risk of instrument fracture.