Hexakis(2,2,3,3-tetrafluoropropoxy)phosphazene (Cas Number 58943-98-9), also known as 2,2,4,4,6,6-Hexakis(2,2,3,3-tetrafluoropropoxy)-1,3,5-triazatriphosphine, Hexakis(1H,1H,3H-perfluoropropoxy)phosphazene and Hexakis(1H,1H,3H-tetrafluoropropoxy)phosphazene, is an organoflourine compound. It is a component of Ultramark 1621, a reference compound for negative and positive ion fast-atom bombardment (FAB) high-resolution mass spectrometry.