Copic ink refill booster for Copic markers. Insures mess-free refilling. Screw it to the top of the Various Ink bottle and insert the needle down the side of the Copic marker broad nib. Refill ink amounts vary for each marker. Caution: very sharp, handle with care. Always recap after use. Not intended for children. Clean Booster with rubbing alcohol or a few drops of colorless blender refill after each use. Use the Copic refill booster to add various ink to any Copic marker without removing the nib or making a mess! Illustrated instructions included. PACKAGE OF 3. Copic Booster for refilling Copic markers.