Arlen Ness Stage 2 Big Sucker Air Cleaner Kit For Harley Twin Cam Arlen Ness Stage II Big Sucker Kits will maximize horsepower and torque by allowing the bike to breathe much better. Using a filter 20 larger than their standard Stage I filter. The Stage II Big Sucker Kit contains all needed hardware, filter, backing plate, gaskets, and even a stylish cover. The Stage II kit is not compatible with the factory cover. Features: Stage II Big Suckers feature a 20 larger filter than Stage I kits for even more airflow Like Stage I kits, each Stage II aluminum backing plate features our patented hidden breather technology and radius air inlet for maximum performance Stage II kits include a custom Ness cover. Factory air cleaner covers will not work Choose from a standard or performance synthetic stainless steel jacketed filter element Each kit includes backing plate, performance air filter, hardware and necessary gaskets Carb E.O # D-639-7