Product Description Ballpoint pens in the past used “sticky” ink, but Anterique’s oil-based ballpoint pens use “ultra-low-viscosity ink” (Mach ball ink). Ultra-low-viscosity is ink that is “smooth” and easy-flowing like salad oil. When using “smooth” ink, an ordinary pen tip will have ink leakage, so it must be combined with an ultra-precisely processed pen tip. Anterique ballpoint pens use a pen tip with a built-in spring to precisely control the flow of ink for a very crisp, non-smudging, ultra-fine .5mm line. This compact mini-size has a total length of 10cm (just under 4 inches) – which makes it easy to pocket and easy to use. 100% made in Japan.