A locking apparatus for connecting a catheter to a stem of an implantable port, comprising: a central axis; a collet sleeve comprising: a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the collet sleeve (21 0), the cylindrical wall comprising: a first recess corresponding to a first locking position of the lockable insert; and a second recess corresponding to a second locking position of the lockable insert; at least one resilient prong protruding inward from the first end and extending into a portion of the center channel of the collet sleeve, each of the at least one resilient prong comprising a gripping surface facing the central axis; and a lockable insert comprising: a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the lockable insert, wherein the center channel of the lockable insert is coaxial with the center channel of the collet sleeve about the central axis, and a locking tab for engaging the first and second recesses (214, 216); and wherein the center channel is adapted to receive the catheter and the stem of the implantable port, wherein the lockable insert comprises a first locking position defined by the locking tab engaging the first recess allowing the lockable insert to move freely along the catheter and stem but preventing the lockable insert from exiting the collet sleeve, and wherein the lockable insert comprises a second locking position defined by the locking tab engaging the second recess so that the cylindrical wall of the lockable insert radially compresses the at least one resilient prong of the collet sleeve to compress the catheter against the stem. a central axis; a collet sleeve comprising: a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the collet sleeve (21 0), the cylindrical wall comprising: a first recess corresponding to a first locking position of the lockable insert; and a second recess corresponding to a second locking position of the lockable insert; at least one resilient prong protruding inward from the first end and extending into a portion of the center channel of the collet sleeve, each of the at least one resilient prong comprising a gripping surface facing the central axis; and a lockable insert comprising: a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the lockable insert, wherein the center channel of the lockable insert is coaxial with the center channel of the collet sleeve about the central axis, and a locking tab for engaging the first and second recesses (214, 216); and a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the collet sleeve (21 0), the cylindrical wall comprising: a first recess corresponding to a first locking position of the lockable insert; and a second recess corresponding to a second locking position of the lockable insert; at least one resilient prong protruding inward from the first end and extending into a portion of the center channel of the collet sleeve, each of the at least one resilient prong comprising a gripping surface facing the central axis; and a lockable insert comprising: a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the lockable insert, wherein the center channel of the lockable insert is coaxial with the center channel of the collet sleeve about the central axis, and a locking tab for engaging the first and second recesses (214, 216); and a first end; a second end; a cylindrical wall defining a center channel about the central axis, the center channel extending from the first end to the second end of the lockable insert, wherein the center channel of the lockable insert is coaxial with the center channel of the collet sleeve about the central axis, and a locking tab for engaging the first and second recesses (214, 216); and wherein the center channel is adapted to receive the catheter and the stem of the implantable port, wherein the lockable insert comprises a first locking position defined by the locking tab engaging the first recess allowing the lockable insert to move freely along the catheter and stem but preventing the lockable insert from exiting the collet sleeve, and wherein the lockable insert comprises a second locking position defined by the locking tab engaging the second recess so that the cylindrical wall of the lockable insert radially compresses the at least one resilient prong of the collet sleeve to compress the catheter against the stem.