Excellent smudge proof and waterproof qualities on almost all surfaces. Dries in seconds, therefore ideal for left handed users. Colour intensive, low odour. Locked tip. Can be left uncapped for days without drying up. Aeroplane safe, automatic pressure equalization prevents pens from leaking on board aircraft. Xylene and toluene free ink. Refillable. Line width is 2mm. Purchasing each unit.