The ornamental design for a penclip, as shown and described.
FIG. 1 is a front bottom side perspective view of a pen clip showing my new design, with the phantom lines depicting environmental structure and forming no part of the claimed design;
FIG. 2 is a front elevational view thereof with the phantom lines depicting environmental structure and forming no part of the claimed design;
FIG. 3 is a left side elevational view thereof which is a mirror image of the right side thereof with the phantom lines depicting environmental structure and forming no part of the claimed design;
FIG. 4 is a bottom plan view thereof with the phantom lines depicting environmental structure and forming no part of the claimed design; and,
FIG. 5 is a top plan view thereof with the phantom lines depicting environmental structure and forming no part of the claimed design.