Karbonius Carbon Fibre Airbox Race - BMW E46 M3 / Z4M (S54)Intake system made 100% in prepreg carbon fibre in autoclave in our facilities in Spain under ISO 9001 Management Quality System rules by qualified staff , which lends the best finished you can find on the market and a major thermal and structural stability. This is possibly one of the best airboxes available in the market. With a built in snorkel, it facilitates the air ducting from the front of the car, getting a lower temperature in the intake