Patent ID: 7041158

Claim:
A filter assembly ( 1 ) for providing a safety air filter arrangement disposed within a primary outer air filter assembly, said safety filter arrangement filtering air when the primary outer filter is being serviced, said filter assembly comprising: a substantially cylindrical filter media ( 4 ) and permeable core ( 3 ) circumscribing a longitudinal axis; and an end cap ( 2 ) secured to a first end of said filter media ( 4 ) and said permeable core ( 3 ); said end cap ( 2 ) having an end portion with a substantially “U” shaped cross-section forming an annular groove for receiving said first end of said filter media ( 4 ) and said permeable core ( 3 ), said “U” shaped cross-section defining an inner lip and an outer lip wherein said inner lip is shorter than said outer lip, wherein said end cap ( 2 ) is formed prior to securing said end cap ( 2 ) to said first end.