Durable ball pen with removable cap Wear-resistant stainless steel writing tip equipped with a disposable, large capacity ink cartridge in oil, waterproof, quick-drying ink-coloured casing elements perfectly adhering to the cap, ventilated cap with a barcode clip placed on each product writing ball with diameter: F (size of writing ball: 0.8mm, writing line thickness: 0.3mm - the following values are approximate.