Perfect for marking patterns on fabric. These chaco pens have a fine point and are narrow just like pen. Easy to hold pens gives a perfect impression on fabric. Washes aways easily and does not leave any residue. The cartridge can be easily removed after its finished, simply unsrew the old cartridge and replace with the new one for further use. You can get all under one roof like liner pens in various colors, cartridge refills, liner refill etc.