Meet Muc-off air filter bio oil. Your engines first line of hardcore defence against dust, dirt and debris trying to sneak into your engine. Engineered for max airflow and next level filtration, this high performance formula traps the filth while keeping your motor breathing fresh and fast with maximum horsepower. It creates a durable, protective layer on every foam cell of your filter, which works even in brutal conditions, yet washes out easily with our air filter cleaner for continued maintenance.