Xiaomi Mi Roller Ball Pen comes with some special features like Switzerland imported refill: smooth writing and smear-proof, retractable and refillable. Japan imported ink: smooth, rich black ink for effortlessly strong impression. 0.5mm fine point draws razor-sharp, consistent lines. 9.5mm contoured grip for superior comfort and control. Handy retractable and rotatable design, convenient to use. All-metal precision connection parts, 50,000 times rotation life test.