The TWSBI Precision Fountain Pen extends the Precision range of mechanical pencils and ballpoint pens. The pen features an aluminium barrel and grip section finished with stainless steel clip and trim. Like the Diamond 580, the Precision Fountain Pen also shares the diamond shaped barrel, which means your pen won't roll off the desk. The Precision Fountain Pen also features TWBSI's famous piston filler mechanism as well as an ingenious ink window so you can monitor the ink level in your pen. Comes with a 1.1 stub.