Cooler box

FIG. 1 is a front view of a cooler box showing our new design;

FIG. 2 is a top view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a rear view thereof; and,

FIG. 7 is a front perspective view thereof.

The broken lines and areas within them in the drawings depict portions of the cooler box that form no part of the claimed design.