The ornamental design for a zippertooth, as shown and described.
FIG. 1 is a front elevational view of a zipper tooth showing our new design;
FIG. 2 is a rear elevational view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a perspective view thereof;
FIG. 8 is a second perspective view thereof;
FIG. 9 is a third perspective view thereof; and,
FIG. 10 is a reduced-scale perspective view showing the zipper tooth in a condition of use with other unclaimed zipper teeth and additional environmental structure assembled together forming a slide fastener.
The broken lines shown in FIG. 10 are used to show unclaimed environment and form no part of the claimed design.