V04 #17 L25 Non-Sterile Endodontic Niti File, 6/Pk. Uniquely designed to allow deep apical shaping and conservative coronal shaping. Designed with a variable 'V' decreasing rate of taper from tip to shaft. More closely mirrors the natural shape of the root versus a constant rate of taper change. Parabolic core design offers strength to guard against separation and high flexibility.