R50, R52, R53 K&N RU1550 Used Air Filter Rubber Filter Used Air Filter can be bolted directly onto the throttle body. Known as a Hot Air Intake (HAI), research and pics in the links below New retails for $50, This used in good condition for $15, shipping $10. (in CONUS USA Only) Paypal Only. HAI Install.... - North American Motoring Operation Hot Air Intake - North American Motoring Can't find an Intake thread. Thanks. - North American Motoring