PTFE Unlaminated Membrane Filters, Hydrophilic, 0.2 Micron. PTFE Unlaminated Membrane Filters, Hydrophilic, 0.2 Micron, 47mm, 100/Pk (H020A047A) Durable, efficient, and broadly compatible, these pure, hydrophilic PTFE membranes are ideal for use with HPLC seperations, aqueous/organic solvents, and many of your other filtration needs.