1. Pen
1.1 is a top and side perspective view of a pen showing my new design;
1.2 is a front elevation view thereof;
1.3 is a side elevation view thereof;
1.4 is a top plan view thereof, the bottom plan view being a mirror image;
1.5 is a partially exploded side elevation view thereof with the cap removed;
1.6 is a fully exploded top and front perspective view thereof;
1.7 is a perspective view thereof wherein the pen is shown configured with other pens into a pyramid structure;
1.8 is a perspective view thereof wherein the pen is shown configured with other pens and objects; and
1.9 is a perspective view thereof wherein the pen is shown configured with other pens into a cube structure.
The broken lines in the drawings illustrate portions of the pen and environmental subject matter of additional pens, paperclips, and a ruler that do not form part of the claimed design.