The Uniball Micro-Air ballpoint pen gives you the freedom of a fountain pen with the security of a roller-ball with no leaks. Unlike other rollerballs, the Air's metal ball is held in a plastic surround, allowing the ball to move without friction when the pen is held at an angle. It is filled with Uni-Ball Super Ink, an advanced ink formula that bonds to paper fibers. It is resistant to chemicals that wash dye-based ink from checks. Super ink is also fade resistant, water resistant, and acid free. Applying light pressure will give a finer line as ink is transferred by the ball itself, whilst firmer pressure allows the ink to flow freely around the ball for a thicker line. The Micro-air pen will give you a finer line width between 0.25mm - 0.45mm, perfect for technical writing or small printing. The sleek, elegant look and feel that is comfortable and easy to grip, and the capped top stays put and ensures that this pen will never leak in your pocket. Black ink in a pack of 3.