I claim the ornamental design for a wet-dry industrial vacuum, as shown.
FIG. 1 is a perspective view of my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a top view thereof; and,
FIG. 6 is a bottom view thereof.
The right side view is a mirror image of the left side view of FIG. 3.
The detachable attachment shown in broken lines is unclaimed subject matter and forms no part of the claimed design or of a specified embodiment thereof.