Professional 0.4mm Nozzle Single Action Gravity Feed Airbrush Made with High-quality Precision Components, better than other dual-action air brushes. Built-in Teflon O-ring for nozzle cap and better for corrosion resistance. One 2cc Eye Dropper for dropping ink or other fluid easily. You can adjust the flow of fluid to unscrew the locked screw conveniently. Air and Fluid Spray: Press the Air/Fluid Control Knob down vertically and pull it back.