The ornamental design for a ratpreventiondevice, as shown and described.
FIG. 1 is an isometric view of a rat prevention device embodying my design;
FIG. 2 is a top plan view of the rat prevention device;
FIG. 3 is a bottom plan view of the rat prevention device;
FIG. 4 is a side view of the rat prevention device;
FIG. 5 is a side view of the rat prevention device;
FIG. 6 is a side view of the rat prevention device; and,
FIG. 7 is an isometric view of the rat prevention device in a position of use.
The toilet depicted by broken lines in FIG. 7 have been shown for the purpose of illustrating environmental features that form no part of the claimed design.