Demonstrator - Transparent and clean, perfect for ink lovers For those who prefer the fluid feel of ink with the convenience of a rollerball tip. With a smooth snap-fit cap and convenient cartridge/converter filling system, the Triad is engineered for effortless use and everyday reliability. Specifications: Ink roller ball pen material: ABS plastic Filling system: cartridge/converter (sold separately) Ink roller ball pen length, closed: 130 mm Ink roller ball pen diameter, barrel: 17 mm Ink roller ball pen weight (without ink): 15 g Gift boxed