Using your K&N drop - in air filter is super easy. Just take out your old air filter from the factory air box and pop this new one in. It's designed to fit right in without any hassle. As for maintenance, when you notice a decrease in performance or the filter looks dirty, it's time for a clean. Wash it gently with mild soap and water, then let it dry completely. Once dry, re - oil it using K&N filter oil following the instructions on the oil bottle. Keep in mind that you should always use K&N recommended products for cleaning and oiling to ensure the filter works at its best. Also, check the filter regularly, especially if you drive in dusty or dirty conditions. This will help your Mercedes run smoothly and keep getting that extra boost of horsepower.