0.05mm Staedtler Pigment Liner : The Pigment Liner is a fine line pen for writing, sketching, and drawing. It features a long metal tip that is ideal for use with rulers, templates, etc. The pen's pigment ink is indelible, lightfast, and waterproof. It's also erasable when used on tracing paper and won't bleed when highlighted. The pen has a metal clip for easy carry and a sturdy plastic barrel for long service life.