Foam cannon. This is one here: www.amazon.com/DUSICHIN-SFL-001-Pressure-Release-Adjustable/dp/B00WPKHFA6/ You must have a high-pressure washer though. There are some for hoses too, but they don't work nearly as well: www.amazon.com/Bunnyk-Foamaster-95QGFMR-75QGFMR-Sprayer/dp/B00BS3GM7I/ ChrisFix shows both of them being used in this video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-CFXfSBR5Q9w.html
