Uniball 12-Piece Air Micro Fine Rollerball Pen Set, 0.5mm, UBA-188-M, Black

The metal ball of the nib is encased in an acetal plastic rather than the standard metal surround which allows for a smoother flow of ink around the ball and an increased flow as further pressure is applied. The revolutionary nib of the Air unlike conventional rollerballs is pressure sensitive meaning that it gives a writing experience and differentiating line width similar to that of a fountain pen. The metal ball of the nib is encased in an acetal plastic rather than the standard metal surround which allows for a smoother flow of ink around the ball and an increased flow as further pressure is applied. The 0.5mm ball delivers a line width of between 0.28mm and 0.45mm (dependent on pressure). Features Uni's high quality "Super Ink" which is not only water and light resistant but also "Tamper-Resistant" meaning that the ink cannot be washed off using chemicals and solutions used by people to fraudulently modify documents. Box contains 12 Black inked pens. Box contains 12 Black inked pens.