The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a tire tread showing our new design, it being understood that the tread is repeated throughout the circumference of the tire, the opposite side perspective being identical thereto;
FIG. 2 is a front elevation view thereof, the rear elevation being identical thereto;
FIG. 3 is a side elevation view thereof, the opposite side elevation being identical thereto; and,
FIG. 4 is a section view of said tire taken along line 4-4 shown in FIG. 2.
In the drawings, the broken lines defining the sidewall, inner bead and the peripheral boundary between the claimed tire tread and the unclaimed sidewall depict environmental subject matter that forms no part of the claimed design. Further, the broken lines on the face of the tire are understood to represent the tread pattern schematically.