Pilot Frixion Pen Refills P1afx725bk, Bulk Pack of 25, 0.7mm Fine, Black Gel Ink Bulk Pack of 25, 0.7mm Fine Black Gel Ink Pilot Frixion Refills. Refills fit Pilot FriXion Ball and Clicker erasable Gel Ink Pens. FriXion ball pens have a unique Thermo-Sensitive Gel Ink Formula that disappears with erasing friction. Rewritable-erase and rewrite repeatedly without damaging documents - No wear or tear! Fine point 0.7mm. Writes smooth, erases clean. The Black FriXion Clicker Pen combines the convenience of a retractable with the incredible FriXion erasable gel ink.