When using the Gundam Marker Airbrush system, there may be a chance that excess paint may spray because too much paint comes out when using the normal nib that comes on the Gundam Marker. By using this item, paint will come out at a steady pace and create a beautifully smooth, painted surface. Each bag comes with 6 special marker nibs. The word nib makes us very mad but we guess that's what we have to call it.