Filter

FIG. 1 is a front elevation view of a filter showing my new design;

FIG. 2 is a back elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a top, front, right side perspective view thereof;

FIG. 8 is another top, front, right side perspective view thereof; and,

FIG. 9 is a bottom, back, right side perspective view thereof.

The broken lines showing portions of the filter form no part of the claimed design.