There are four parts to the Cope needle.

The first part is the outer cannula . It has a cutting edge that facilitates the biopsy of the pleura. The outer cannula is hollow and creates an entry poi

The two thinner pieces are used to create a stylet. The solid thin obturator is placed inside the hollow trocar and, together, are placed into the outer cannula.

The last piece to the Cope needle is the biopsy trocar . This trocar has a hook on the end that is used to take the actual biopsy. The guard that can be adjusted in position over the outer cannula to control the distance entered.