The CJ-9619 CoilJet Foaming Nozzle Creates a Thick, Rich Lather to Lift Dirt and Debris from Coils. This Nozzle is Designed to Add Air to the Spray of Foaming Coil Cleaner, Increasing Foam Levels and Helping Lift and Remove Dirt from HVAC and Refrigeration Coils. Best used with SpeedyFoam Coil Cleaner