PEEK (polyether ether ketone) is a high performance polymer belonging to the group of polyarylether ketones (PAEK), which meets all requirements of HPLC applications with respect to chemical resistance and mechanical stability. In some fields of application in HPLC, like e.g. in ion chromatography and chromatography of biopolymers, PEEK fulfills the requirements for a non-metallic material. All fittings can be tightened by hand.