Arlen Ness Slot Track Stage 1 Big Sucker Air Cleaner Kit For Harley Touring With EFI This Arlen Ness Big Sucker Kit in a black finish with a Slot Track steel cover has an all-in-one backing plate with carb support and built-in breather tunnels. The patented Big Sucker technology has tunnels that exit at the mouth of the carb or throttle body to create a virtually closed-loop system for the best performance possible. The Black Finish Stage I kit includes a black aluminum backing plate and Team Ness round tapered high flow synthetic air filter. Features All in one backing plate features a built in throttle body support and built in breather tunnels Tunnels exit at the mouth of the throttle body to create a virtually closed loop system Backing plate has o-ring breather bolts and a radiused intake manifold Kit includes a anodized black aluminum backing plate, Team Ness high flow air filter and all necessary hardware Stage I features a tapered round air filter and a anodized black billet aluminum air filter cover with a slot track design Carb E.o. # D-639-7