MAF adapter for a 335d to a 4" flange cone filter. Takes the oval and turns it into a circle for mounting a cone filter. I used RTV silicone to attach it to the MAF (it's a very tight fit), once it sets clamp on your filter. Designed so the air is funneled in... Use the tool only for the documented engine or transmission, keep it square and follow the BMW service procedure and torque values.
