If you want to clean your Preval Sprayer, you can simply clean the system by spraying your paint thinner alone for 10 seconds.  Paint thinner is the product used to condition the paint to allow for better spray flow.  Thinners include water, acetone, mineral spirits and/or lacquer thinner. Whatever thinner is used for what you are spraying, you can also use for cleaning. Use the proper cleaning agent as specified by the manufacturer for the paint liquid you are using. If you do not properly clean your Preval Sprayer you wll have trouble using it in the future as any contamination will reduce the Preval Sprayer output or even clog it completely.  If the Sprayer is clogged rput your finget on teh red insert inside of the button nozzle and cover it.  While covering it, press down on the button to force air in a reverse manner which helps clogs.  If that doesn't work.  remove the product contaner by twisting it off the Sprayer hold the sprayer upside down and try to spray propellant.  Cleanliness is even more important on the inside of the button. If this occurs, please take off teh button and soak it is thinner and use a qtip to clean around the insides.  Cleaning the glass and plastic jars is easy.