Staedtler  - Triplus Fineliner Pen Pack of 20. The Staedtler Triplus Fineliner is a superfine long-lasting pen with water based ink. The Staedtler Triplus Fineliner produces a 0.3mm line. With a metal-clad tip and ergonomic triangular barrel the S taedtler Triplus Fineliner provides effortless and fatigue free usage, ideal for people who spend a lot of time writing or drawing, making it ideal for home, office or student everyday usage.Staedtler Triplus Fineliner ink washes out of most textiles and its clip PP barrel guarantees long service life.