Excelvan 1.4mm Professional 3PCS HVLP Air Spray Gun Kit Gravity Feed Paint Sprayer Fine Adjustment: 3 Knobs for full adjustment: Fluid, Pattern and Air Pressure Controls. The desired pattern and fine atomization can be easily obtained by regulating the Pattern Adjusting Knob and Fluid Adjusting Knob Pattern Adjustment: Turn the Pattern Adjusting Knob to the right until tight will make spray pattern round, or turn left make spray pattern ellipse Fluid Adjustment: Turn the Fluid Adjusting Knob clockwise will decrease the volume of fluid output and counter-clockwise will increase fluid output