Available in pore sizes from 0.1 um to 0.45 um and multiple diameters, Sartorius is sure to have a polyethersulfone (PES) membrane filters for nearly your every need. Suitable for aqueous & solvents. Sterilization by Autoclaving. Chemically resistant over a wide pH scale (1-14) Very low extractables. Multiple pore sizes & diameters available.