Inside the robust aluminium barrel of each pentel Pentel N50S Fine Bullet Point Permanent Markers N50S-A Black is quality Pentel indelible ink that writes smoothly on almost any surface from plastic and metal, to glass. The fine bullet tip is ideal for general purpose use in industry or commerce. The 3.18mm bullet tip writes between 0.5-1.0mm line width. This pack contains 12 black markers.