The diffuser works in conjunction with other aerodynamic components of the car to help generate downforce. As the car moves forward and pushes air out of the way, the air molecules at the rear of the car are disturbed, creating a Â
To direct the high-speed airflow coming from under the car, the diffuser redirects the high-speed air to transition smoothly into the low-pressure vacuum at the rear. This creates smoother airflow under the car, enhancing the performance of other aerodynamic components such as aerodynamic wings.
Before Ordering
〇 Regarding Import Consumption Tax
At the Shaftoya shopping site, we pay the import consumption tax incurred at the time of import on your behalf, so there will be no additional charges beyond the total amount paid at checkout.
〇Compatibility Check
Our entire product database is based on North American vehicles (USDM). Please confirm whether or not parts can be installed on Japanese vehicles (JDM) before placing your order. (If you are unsure whether a listed product is compatible with your vehicle, please feel free to contact us. Our support team will be happy to assist you.)
If you place an order without confirming compatibility, we cannot accept returns due to incompatibility.
Please note that even if products are filtered by selecting the year, manufacturer, and vehicle model using the tabs on our top page, this does not necessarily mean they will fit Japanese model vehicles without modification.
All products have been translated into Japanese using translation software. As there may be confusing expressions, please contact us before ordering if you have any questions.
○ Regarding Shipping
Shipping costs are paid at the time of checkout. Shipping estimates are automatically calculated once you enter your shipping address on the checkout page. For large items such as body parts, there may occasionally be a significant discrepancy between the automatically calculated shipping cost and the actual shipping cost. In such cases, we will contact you individually via email.
All products are generally shipped internationally from our U.S. warehouse. Unlike domestic shipping in Japan, international shipping takes approximately 7 to 14 days, so please allow plenty of time for your order. If you are in a hurry, please contact us in advance to check the lead time. Please note that all products are transported by air. They are not shipped by sea.
○ Regarding Compliance with Japanese Vehicle Inspections (Shaken)
Please note that all products we handle are designed and manufactured outside of Japan. They are not designed to comply with the "Japanese Vehicle Inspection System," and we are unable to provide strength study documents or similar paperwork for these inspections. Therefore, all parts are sold for "use on circuits, private land, or off-road," and installation and use are at your own risk.
○ Regarding Warranty
Please check the contents immediately upon arrival. As all products are shipped internationally from outside of Japan, there may be shipping damage to the packaging or the products themselves. Please understand that we will only provide returns, refunds, or exchanges for products with shipping damage, defects, or incorrect items if you contact us within 7 days of receipt. Furthermore, for products sold through us, warranty support will be handled "exclusively through us." Please note that we do not coordinate with other companies or agencies located within Japan for such support.