Pack of 4, Tombow 55691 O3p X-fine 0.3mm Black Rollerball Refills
Pen refill for all Tombow roller ball pens. Permanent, waterproof, fast-drying Black pigment Ink won't smear, skip, or fade. Tungsten carbide rolling ball for smoothness. Fine Point 0.3 mm tip for precision writing. Comes with one refill pack.