Combi syringe filters are recommended for solutions with a high load of particulate matter or for highly viscous solutions. These products combine a coarse glass fiber prefilter and a small-pore polyester (polyethylene terephthalate) membrane as main filter. The hydrophilic multipurpose PET membrane is suitable for polar as well as nonpolar solvents. It is the HPLC filter, especially suited for mixtures of water and organic solvents. All CHROMAFIL filters are autoclavable (121 °C and 1.1 bar for 30 min)!