The classic Twin Air Liquid Dirt Remover is designed to wash filters oiled with Twin Air Liquid Power filter oil in the best possible way. Keep your Twin Air air filter clean with Liquid Dirt Remover to protect your engine for a long life. Designed to quickly dissolve dirt and grease from your filters. Will not harden or damage your air filters like solvents or gasoline will. Solvent free. 4 liters.