The ornamental design for a petstand for vehicles, as shown and described.
FIG. 1 is a front, right perspective view of a pet stand for vehicles showing my new design.
FIG. 2 is an orthogonal front view of the pet stand for vehicles of FIG. 1.
FIG. 3 is an orthogonal rear view of the pet stand for vehicles of FIG. 1.
FIG. 4 is an orthogonal left side view of the pet stand for vehicles of FIG. 1; the orthogonal right side view of the pet stand for vehicles of FIG. 1 is the mirror image of FIG. 4.
FIG. 5 is an orthogonal top view of the pet stand for vehicles of FIG. 1.
FIG. 6 is an orthogonal bottom view of the pet stand for vehicles of FIG. 1; and,
FIG. 7 is a front, top perspective view of a pet stand for vehicles in an environment showing my new design. The broken lines showing a portion of a vehicle's interior and a leashed pet are for illustrative purposes only and form no part of the claimed design.