Robert Oster Thunderstorm is a premium fountain pen ink known for its deep, storm-inspired tone and reliable performance on fountain-pen-friendly paper. This rich bluish-gray colour delivers balanced saturation with subtle shading variation, making it suitable for everyday writing, journaling, planning, and creative projects. Formulated for smooth, consistent flow and minimal feathering, Thunderstorm performs dependably across a variety of nib sizes and writing styles. Features • Premium fountain pen ink from the Robert Oster Signature line • Deep bluish-gray colour with balanced saturation • Smooth, consistent flow ideal for writing and creative use • Subtle tonal variation enhances expressiveness on the page • Performs well on fountain-pen-friendly paper with minimal feathering • Lightweight, durable PET plastic bottle for easy handling • Wide bottle opening for comfortable filling • Made in Australia Specifications • Colour: Thunderstorm (deep bluish-gray) • Volume: 50 ml • Ink type: Dye-based fountain pen ink • Bottle: PET plastic bottle with screw cap • Suitable for: Fountain pens (clean thoroughly when switching inks) Non Waterproof See all Robert Oster products
