The Uni-ball ZENTO is a soft-writing water-based ballpoint pen equipped with newly developed ZENTO ink. It provides a stress-free, smooth writing experience. The Signature model features a magnetic cap that clicks off the pen body. Ink color: Black. Nib diameter: 0.5 mm. Refill: UBR-Z-05. Dimensions: Height = 120 mm, Width = 14 mm, Thickness = 13 mm. Product color: Black.