Foam Cannon with 1/4 Inch Quick Connector. Fill some FalconPro Car Wash Soap into the bottle with warm water to get thick foam; Then connect 1/4" quick connection plug to Pressure Washer Gun or Wand. Finally, adjust the knob on the top to desired foam level and then foam sprayer will disperse thick foam. The knob adjusts the foam dispensing amount, and the nozzle adjusts the sprinkle pattern. Adjustable nozzle for accurate mixing and foam generation. Turn the top knob right (-) to get the thickest mixture, adjust the nozzle to get a proper sprinkle pattern, and let it loose.