Refillable liquid ink roller X77 Liquid ink roller, liquid ink conforms to ASTM D-4236 Tip: Stainless steel conic tip Ball: 0.5mm/0.7mm Clip: metal Ink color : Blue, black, red, green Proposed packing: 12pcs/dozen box, 864pcs/carton Advantage: Precise writing smooth to the last drop of ink at any angle. Refillable . Transparant apperance, ideal for both office and students.