Commonly thick walled, with pointed ends and bordered pits that have lenticular to slit-like apertures. If both libriform fibers (PO:0004520) and fiber tracheids are present, the libriform fibers usually have thicker walls. Fiber tracheids have bordered pits with smaller pit cavities than the vessel members (PO:0002003) or tracheids (PO:0000301) of the same wood and a distinct pit cavity leading from the pit cavity to the cell lumen through the thick cell wall.

A tracheary element (PO:0000290) that is part of a xylem vessel (PO:0025417) and has as parts perforation plates.