Fudenosuke Firm Tip Brush Pen features a firm yet flexible brush tip for different lettering and drawing techniques. Create extra-fine, fine or medium strokes by a change in brush pressure. Great for calligraphy and art drawings. Barrels are made of recycled polypropylene plastic. Twin tip – water-based, pigmented black and grey ink. Fine line. Odorless. Non-refillable. - Dual brush tips – one black ink and the other grey ink - Great for calligraphy and art drawings - Water-based - Pigmented black and grey ink - Made of recycled polypropylene plastic - Fine line - Odorless