Alvin - TechLiner - Technical Drawing Markers - 3 Pen Set - TechLiner Technical Drawing Markers by Alvin contain extremely fine polyacetal plastic nibs set in 0.5mm stainless steel sleeve for smudge-free inking. TechLiner Drawing Markers are ideal for precision drafting, free-hand drawing, or any design work. Water-based pigment ink is non-bleeding, waterproof, and fadeproof. The acid-free, archival quality ink is also quick drying and lightfast. These disposable technical pens are offered in five line widths. Alvin is one of the primary sources for drafting supplies and drawing equipment in the country. Creative Coldsnow is a pround retailer of Alvin graphic arts, drafting and fine arts products.