The 21-821DS Performance Cold Air Intake System produces horsepower and torque gains by replacing the restrictive air filter and air intake housing. This air intake system was designed, tuned and dyno-tested to fit specific Nissan 370Z models. This system replaces both the left and right side intakes. The AEM Dryflow synthetic washable air filter does not require oiling and can be used up to 100,000 miles before servicing is needed (depending on driving conditions). The heatshield is a two piece design and also utilizes the factory air ducting. The intake tube is constructed from mandrel bent aluminum and has a durable gray powder coat finish. This air intake system was developed to accommodate the mass air flow sensor and PCV hose. The air intake system is backed by AEM's Lifetime Limited Warranty. Some AEM air intakes are not legal for sale or use in California and other states adopting California emission standards, while others are 50 state legal. View the 21-821DS vehicle applications to determine the legal status for each vehicle.