A filtering system for water treatment including a head member having inlet and outlet ports and replaceable, disposable filter cartridge for insertion into the head member, the filter cartridge including a dual lug retaining system for retaining the filter cartridge in the head member, one of said lug...http://www.google.es/patents/US4956086?utm_source=gb-gplus-sharePatente US4956086 - Filter cartridge with a lugged concentric closure portion
Filter cartridge with a lugged concentric closure portion
