Filter with retained safety element

The invention relates to fluid filters, and more particularly to filters having a safety or secondary filter element in addition to a primary or main filter element. A filter () has a housing () extending along an axis () between first and second axial ends (and ), and has a closed loop primary filter element () extending axially in the housing, and a closed loop safety filter element () in the hollow interior () of the primary filter element. A detent member () engages and retains the end cap () of the safety filter element independently of the primary filter element to retain the safety filter element in housing upon removal of the primary filter element from the housing.