The secret behind the Kaweco Sport ICE fountain pen lies in its cap. The smart design allows the pen to be a compact pocket-size when capped and when uncapped it posts at the perfect length for writing. The cartridge filling system is easy to use with your favorite standard international fountain pen ink cartridges. Comes with one ink cartridge. Silver-colored steel fine nib. Optional clips are sold separately. Approximate pen size as follows: Length Capped: 4.2" Length Posted: 5.2" Barrel Diameter: 0.4" Cap Diameter: 0.5"