Length without shipper cap 109.25 mm Diameter without shipper cap 7 mm Writing tip: Extrusion moulded POM with stainless steel adapter. Front section: Polypropylene (PP), Black. Refill system: Advanced absorber technology; constant flow. Ink: Waterbased, light-resistant and water-resistant (not water-proof) Exclusivity: Exclusive design. Can be used only with specifically designed nib assembly. Ink Flow: Stable, regular ink flow throughout the life of the refill Altitude test: No leakage (for example under airplane flight conditions) Thermal shock cycle: No leakage (for example under heated car condtions) Flexibility of front area: Flexible up and down movement of front area, gives a fountain pen nib like feel.