Double pen

The pen is contained to hold two bic tips without any modification

Features

This pen is not much wider and higher than a bic, and the Caps are designed to protect the tip of the pen from bumps. The hole in the cap of the pen serves to regulate the internal pressure and the fact that it is asymmetrical allows the two points of the pen to be distinguished. 

Quality

I recommend use a layer high of 0.16 mm or less and a layer width of 4 mm or less. 

Direction

I recommend printing the pen horizontally to make the print much more durable.