STAEDTLER triplus fineliner has a superfine, metal-clad tip. Designed with an ergonomic triangular barrel for effortless, fatigue-free writing. The unique DRY SAFE feature of the water-based inks enables pens to be left uncapped for days at a time without drying up. Line width approx. 0.3 mm. 6 1/4" long.Triplus Fineliner Pens, 0.3mm, Metal Clad Tip, Staedtler Triplus Color marker and pen is acid-free with water-based ink and ideal for drawing, coloring in the classroom or adult coloring books. Staedtler Triplus Color marker and pen features triangular barrel for fatigue-free writing and the fineliner pen features line width of approximately 0.3 mm. Marker contains dry Safe ink and can be left uncapped for days without drying up.