The ornamental design for a lunchbox, as shown and described.
FIG. 1 is a perspective view of the lunch box of this invention.
FIG. 2 is a perspective view of the lunch box of this invention with the cover flap open.
FIG. 3 is a front elevational view of the lunch box shown in FIG. 1
FIG. 4 is a rear elevational view of the lunch box shown in FIG. 1.
FIG. 5 is a side elevational view of the lunch box shown in FIG. 1; and,
FIG. 6 is a plan view of the lunch box shown in FIG. 1.
The broken lines in the drawings on the side surface of the lunch box visible in FIGS. 1, 2 & 5 represent stitching and are included as part of the claim.