The Hugo Boss blue pen refill (6 units) ensures smooth, flawless writing with your favorite Hugo Boss writing instruments. Made with high-density, quick-drying blue ink, this six-cartridge pack ensures a consistent flow that prevents smudging. The ink formulation preserves the integrity of the ink cartridge feeder over time. It's an essential consumable for professionals and students who use their Hugo Boss blue ink pen daily and want to maintain its original performance.