Using Scrubby Soap is great for regular maintenance of your paint brushes but sometimes you need more help. Clean As A Whistle is a non-flammable, non-toxic, biodegradable brush cleaner and conditioner. All you need to do is pour enough CAAW in a jar to cover your bristles and soak for several hours and scrub hardened paint residue out. For regular maintenance, use a 50/50 water/CAAW. Repeat soak-scrub if needed. When clean in soap & water then rinse. Reshape bristles and lay flat or hang to dry.