PTFE Vent Filter, Sterile, 0.45 Micron, 50mm, 1/4 in to 3/8 in hose BARB, 10/Pk PTFE Vent Filter, Sterile, 0.45 Micron, 50mm, 1/4 in to 3/8 in hose BARB, 10/Pk Easy-to-use, sterile ,and disposable, these In-Line Filters contain a hydrophobic PTFE membrane ideal for confining and isolating infectious and hazardous material in vacuum systems and venting applications.