You're not the first one. Pretty sure you can't buy just that part from Nissan. It is part of the intake tubing. The part number is 16576EY00B. Like DR said, you might find it from someone on the forum who has replaced their intakes with a CAI.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |