The Sonax 5 Gallon Bucket with a Grit Gaurd removes contaminant build up on your wash mitt or sponge. With every pass on your vehicle, more and more dirt gets trapped into the fibers of your towel, sponge, or wash mitt. With the Sonax Bucket and Grit Gaurd combo, you won't have to worry about your paint getting scratched from dirt and debris. Just rub your favorite washing utility against the Grit Gaurd, and the dirt gets trapped beneath.