The uni-ball AIR Micro rollerball pen from Mitsubishi Pencil offers a pleasantly smooth writing experience, similar to that of a fountain pen, and allows for variable line width depending on the pressure applied. The felt tip varies between 0.2 and 0.45 mm, depending on the pressure exerted. The ink in pink is archival quality and provides clear, precise lines. The barrel of the pen is made of gray plastic and is round, while the rollerball is equipped with the innovative Free Ink System, which ensures a consistent ink flow.