LOFTREX™ melt blown polypropylene filter cartridges have a multi-density design to simultaneously retain both coarse and fine particles. The outer portion consists of non-woven melt blown polypropylene for retention of larger particles. The inner area consists of a bi-component polypropylene and polyethylene fiber inner core to retain the finer particulate that traversed through the melt blown section. LOFTREX™ are constructed as a single piece, it is not a two piece design with an inner core. No surfactants are present which could contribute to foaming or other undesirable performance and the material of construction satisfies FDA CFR 177 requirements LOFTREX™ filter cartridges are offered in four designs encompassing both nominal and absolute rated retentions and single and multi-zone designs for retentions within 0.50 to 150 microns.