Stylet
: a thin wire inserted into a catheter to maintain rigidity or into a hollow needle to maintain patency.
Stylets are used inside an endotracheal tube to give it a certain shape which aids navigation of the tube towards the laryngeal inlet.
. The standard endotracheal tube's 'natural' curvature is usually bent enough for most cases of laryngoscopy to place the tube through the vocal chords without loading it onto a stylet.
stylets are malleable, are also rigid intubating aids.