The ornamental design for a zippertab, as shown and described.
FIG. 1 is a front perspective view of the present embodiment;
FIG. 2 is a front elevation view of the present embodiment, the rear elevation view being a mirror image thereof;
FIG. 3 is a left side elevation view of the present embodiment, the rear elevation view being a mirror image thereof;
FIG. 4 is a top plan view of the present embodiment; and,
FIG. 5 is a bottom plan view of the present embodiment.
The broken lines shown in the drawings illustrate portions of the zipper tab that form no part of the claimed design.
The zipper tab is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claimed design.