FEBI AC Filter for Mercedes Benz S-Class W221 2009-2023 The Febi AC filter is a high-quality cabin air filter designed to effectively trap dust, pollen, and other airborne particles, ensuring clean and healthy air inside the car's cabin. It meets or exceeds OEM specifications for proper fitment and performance. Made with durable materials, it provides efficient filtration for extended use. Regular replacement is essential to maintain optimal air quality and HVAC system performance.