The file 'Mostly Printed CNC -Add On- Pen Holder 3D Printer Model' is (STL) file type, size is 26.5KB.
Pen holder for the CNC.http://www.thingiverse.com/thing:724999
Flexible pen holder, has some give to it to keep even pressure on your surface. Uses 2 cable ties or similar to hold any size pen, pencil, marker.