200pcs PTFE Membrane HPLC Syringe Filters 25mm 0.22μm No-Sterile 10-100pc PTFE Syringe Filter 13mm 25mm Diameter, 0.45 um 0.22 um Pore Size, HPLC. Syringe Filters – EmbioTec. 13, 30. ReZist. ~ PTFE for HPLC sample prep. PTFE. 13, 30. SPARTAN Syringe filters are available in 4, 10, 13, 25, and 30 mm sizes – not all Whatman Puradisc