Air filter

FIG. 1 is a perspective view of an air filter showing our new design configured vertically;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a bottom plan view thereof; and

FIG. 7 is a top plan view thereof.

FIG. 8 is a perspective view of the variation of the air filter showing our new design having a horizontal configuration;

FIG. 9 is a front elevational view thereof;

FIG. 10 is a rear elevational view thereof;

FIG. 11 is a left side elevational view thereof, rotated 180 degrees in the plane of the page;

FIG. 12 is a right side elevational view thereof, rotated 180 degrees in the plane of the page;

FIG. 13 is a top plan view thereof; and,

FIG. 14 is a bottom plan view thereof.

The broken lines shown in the drawings are for the purpose of illustrating portions of the article that form no part of the claimed design.