Cello Butterflow Roller pen pack contains 4 pens (3 blue, 1 black) and 2 refills (1 blue & 1 black). With an advanced cartridged system, the Butterflow Roller pen packs a premium writing experience. Introducing the 1st Jumbo refill, this pen delivers a long writing experience. The Roller pen ink is indicated on the center of the pen. With its stylish design and the Butterflow promise of smoothness, this roller pen will redefine smoothness in your writing.