Filson 0.22 micron PTFE filter is ideally designed to remove most contaminants, especially bacteria. Our 0.22 micron PTFE filter can be made of booth hydrophobic and hydrophilic PTFE, so you can choose appropriate material based on your unique application. Material: Polytetrafluoroethylene ; Micron Rating: 0.22 micron; Porosity: 85%