Gel Impact RT Retractable Pen Refills, Bold Point, Blue Ink, Pack of 2. For all uni-ball Gel Impact Retractable pens. Gel ink combines the durability of a ballpoint with the smooth nature of a roller-tipped instrument. Acid-free ink is fade-proof and water-resistant. Consistent, premium-quality performance with every refill. 0.6 inches long by 2.12 inches wide by 7.62 inches high. 0.03 pounds. Related search terms for this product include: uni ball, uni-ball, retractable pen, gel pen, ink pen.