I love this pen! It is a new addition to my nature journaling kit because it has permanent waterproof ink so I can watercolor over it, and it has a wonderful, flexible tip–if I press hard, I get a thick line and if I press lightly, I get a thin line. I love the variety of line textures it offers. It is great for lettering, too!
The barrels are made of recycled polypropylene plastic. They feature water-based, odorless pigmented black ink. Non-refillable.