Air and Fuel› Air Cleaners, Filters, Intakes and Components
K&N Engineering
K&N 99-09 Honda TRX400EX/X Replacement Air Filter
SKU: K001 HA-4099
Beginner — under 30 min
Description
This performance air filter features a round tapered shape with a 3-inch flange inside diameter. Its dimensions include a large end diameter of 5.375 inches, a base outside diameter of 5.125 inches, and a height of 4.5 inches. The filter is intended to provide increased horsepower and acceleration.
Fitment
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Specifications
| Brand | K&N Engineering |
| Part Number | K001 HA-4099 |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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