The uni-ball Signo Gel Grip is a high quality gel ink rollerball pen. It features a rubber grip for comfort and has an ink window incorporated into the barrel design so that you know when you need a refill. The Signo Gel Grip also contains uni Super Ink, which is fade resistant, water resistant and tamper proof.. Medium (0.7 mm) line. High quality gel ink rollerball. Contains uni Super Ink; fade resistant, water resistant and tamper proof. Rubber grip for comfortable writing