Anterique Oil-Based Ballpoint Pens are innovative, Japanese ballpoint pens that combine Mach Ball black ink with vintage-inspired forms. Inspired by the classic American ballpoint pens of the 1960s, the BP1 Ballpoint Pen is a great every day pen for work or study. Ballpoint pens in the past used "sticky? ink, but these oil-based ballpoint pens use "ultra-low-viscosity ink" (Mach ball ink).?"Ultra-low viscosity" is ink that is extremely smooth.?To prevent leaking, the special ink is combined with an ultra-precision roller ball. These pens also feature a built-in spring to precisely control the flow of ink. Crafted with a lightweight plastic?body these pens offer?a smooth writing experience?that's reliable and comfortable. Comes in many vibrant colors to match your personal style.