A cannula, such as an IV catheter introducer needle, that has a bi-directionally engageable crimp feature is described herein. The feature comprises a maximum outer diameter that is greater than an outer diameter of the cannula. Additionally, the feature comprises a proximal side and a distal side. The larger outer diameter of the proximal side can act as a proximal engagement that prevents the cannula from being entirely extracted in a proximal direction from a cannula shield. The distal side of the feature can comprise a notch that acts a distal engagement, which prevents the cannula from reemerging distally from the shield, once the cannula has been pulled into the shield. The notch can include an engagement surface that extends laterally past the cannula's outer diameter. The engagement surface can be configured to run substantially perpendicular to the cannula's longitudinal axis.