One of the major applications for the PTFE (Type WTP) filter is the clarification of corrosives, solvents and aggressive fluids. This includes the important requirement in HPLC analysis for sample filtration where any solid particles can cause permanent damage to the column. The 0.5¬µm pore size is normally used. Air and gas sterilization make use of the hydrophobic characteristics of PTFE membranes and their ability to stop aqueous aerosols. Usual pore sizes are 0.2¬µm and 0.5¬µm. Sterile venting of vacuum manifolds, fermentation vessels and sterile filtrate tanks and containers utilize PTFE 0.2¬µm membranes. Made from polytetrafluoroethylene (PTFE) stretched film, laminated to a non-woven polypropylene support web. These filters offer chemical stability, high temperature stability (145°C) and hydrophobicity. 100/box.