Pilot G2 Retractable Premium Gel Ink Roller Ball Pens, Ultra Fine Point, Black Ink with 6 refills G2 writes longer than the average of the top branded gel ink pens.** **Independent third party ISO testing. Average of G2 write out (all point sizes) compared to the average of the top branded gel ink pens tested (all point sizes). Data on file with Pilot Corporation of America. Contoured rubber grip for writing comfort Fits G2, G2 Limited, G2 Pro, G6, Dr. Grip LTD., Dr. Grip Gel, Precise Gel BeGreen, G-Knock BeGreen, Q7, B2P Gel Ink pens, ExecuGel and Pilot MR Gel Roller Dynamic Gel Ink Formula that is smooth writing and smear-proof with a ultra fine 0.38mm point