Plenum Box

FIG. 1 is a perspective view of a plenum box;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a right side view thereof.

The dashed lines in the drawings represent environmental structure and features that form no part of the claimed design.