The ornamental design for a penclip, as shown and described.
FIG. 1 is a front bottom side perspective view of the pen clip showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a side elevational view thereof;
FIG. 4 is a back elevational view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a top plan view thereof.
The broken lines showing the barrel of a pen illustrate environmental matter, and the circle drawn in broken lines in FIG. 6 that shows the bounds of the claim, form no part of the claimed design.