Upgrade from the stock BMW N55 charge pipe to the MAD N55charge pipe for maximum airflow and reliability! The stock BMW N55 charge pipe is plastic and prone to failure. It's only a matter of time before the charge pipe to break. The MAD N55 charge pipe is a strong aluminum piece; it will provide better airflow and won't fail, and fits like stock. The MAD charge pipe retains the BMW C-clip and O-ring for the best fitment. Do not forget to move them from the stock charge pipe to the MAD option. The MAD charge pipe comes with two meth bungs; both bungs are sealed. If you do not intend to use methanol injection, keep them closed. Features: Better airflow More robust material (aluminum vs. plastic) Two meth bungs Lifetime warranty on defects and fitment 90 day return period All orders ship in 1-2 business days Spot on fitment Fitment: 2011-2013 135 2011-2013 335i & Xdrive (E chassis)