30ml nib cleaning fluid. Specially formulated to break up stubborn blockages in pen nibs. Directions for use: Submerge the pen nib directly into the solution, wait a few minutes to allow the fluid to soak in, rinse pen thoroughly with warm water. Flush the pen through with the fluid, repeat until the pen is clear of any blockages, rinse the pen thoroughly with water. For best results use the solution neat. Made in UK.