Stabilo Bionic Rollerball Pen Refill - Blue Ink REFILL INK FOR STABILO BIONIC ROLLERBALL PEN - Stabilo refill for bionic rollerball pen, blue. ADVANCE LIQUID-INK TECHNOLOGY - This pen ink ensures that the pen glides across the page without scratching or blotching. HIGH-QUALITY ROLLERBALL TIP - Rollerball tip provides the highest precision  glides smoothly across the paper and does not scratch. PRECISION WRITING - it has 0.4 mm tip that provides the highest precision in writing. 4 DIFFERENT COLORS - Available in four popular colors: red, black, blue and green