The Uni-ball Vision Elite roller ball pen features the Uni-flow ink system, which creates a steady flow of water-resistant ink and smooth, consistent color. The pigment-based ink forms an indelible bond to paper, resulting in strong colors and document security. It is resistant to chemicals that can wash away dye-based inks, thus preventing check washing (a common method of check fraud). The ink is acid-free, fade-resistant, and of archival quality, ideal for valuable documents. The pen is airplane-safe—a protective reservoir inside the barrel keeps air from expanding in the ink tube, thereby preventing in-flight leaks. The sleek durable metal clip, bend-resistant stainless steel tip, and tungsten carbide roller ball enhance the look and performance of the pen