Octopus Highlighter Ink in Neon Yellow offers a sustainable, vegan alternative for highlighting with fountain pens, converters, brushes, and markers. Ideal for precise highlighting of small text like laws or the Bible, it delivers vivid color with strong luminosity that resists fading, water, and erasing. Compatible with piston and calligraphy nibs, this indelible ink combines high saturation with durability for long-lasting, bright marks.