The ornamental design for a productdisplaystand, as shown and described.
FIG. 1 is a perspective view of the product display stand of the invention with associated product containers being shown in phantom lines as not forming a part of the invention;
FIG. 2 is a front view of the product display stand of FIG. 1;
FIG. 3 is a left side view of the product display stand of FIG. 1, the right side view being a mirror image thereof;
FIG. 4 is a back view of the product display stand of the invention;
FIG. 5 is a top view of the product display stand of FIG. 1; and,
FIG. 6 is a bottom view of the product display stand of the invention.
The broken lines are for illustrative purposes only and form no part of the claimed design.