SPOON AIR CLEANER Intake For HONDA CR-Z ZF1 ZF2 17220-ZF1-000Brand SPOON Series Name AIR CLEANER Product Descriptions The air inhaled at full throttle opening is huge and super fast. On the other hand, when the throttle is OFF, inertia works, and the intake air is compressed in front of the closed throttle. The next time you open the accelerator, the negative pressure becomes larger than the sealed cleaner box with the compressed recoil, resulting in higher filling efficiency. Thus Honda NA's inspiration system