Full flow filter

A full flow fluid filter comprising a housing extending axially along an axis, a pleated filter element having a plurality of pleats in a closed loop having an outer perimeter defined by a plurality of outer pleat tips, and an inner perimeter defined by a plurality of inner pleat tips, said loop having a hollow interior extending along said axis, said pleats forming wall segments extending in serpentine manner between said inner and outer pleat tips, said wall segments extending axially between upstream and downstream ends, said wall segments defining axial flow channels therebetween, said upstream ends of said wall segments being alternately sealed to each other to define a first set of flow channels open at said upstream ends, and a second set of flow channels interdigitated with said first set of flow channels and closed at said upstream ends, said downstream ends of said wall segments being alternately sealed to each other such that said first set of flow channels have closed downstream ends, and said second set of flow channels have open downstream ends, such that fluid flows substantially directly axially through said filter element, through said open upstream ends of said first set of flow channels then through said wall segments then through said open downstream ends of said second set of flow channels.