Easy to Use: The SIMPSON Foam Cannon is the perfect addition to your toolbox for DIY projects; Clean like the pros with adjustable spray patterns and foam thickness; Perfect to use for soap applications for your vehicle, siding, boats, RVs, UTVs and more Compatible with Most Pressure Washers: The foam cannon is compatible with most cold-water gas or electric pressure washers rated up to 4000 PSI; For optimal foam, the pressure washer should produce no less than 1600 PSI How to Use: Add approved detergent to the soap container; follow the soap manufacturer's recommendations for dilution and use; Connect QC plug to pressure washer wand; Adjust the pattern by twisting the nozzle; adjust foam thickness by rotating the knob How to Clean After Use: To prevent chemical damage, run clean water through the foam cannon after use for at least 30 seconds until all parts are rinsed clean Specifications: Heavy-duty brass fittings with a standard 1/4" QC plug; Designed to be used with a minimum pressure range of 1,600 PSI to maximum of 4,000 PSI; Container Capacity: 1 Liter (33 oz); For cold-water use.