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    K&N Universal Air Filter | Clamp-On Conical, 3.75in Flange, 5in Tall | RU-4250

    Vendor: K&N
    Part Number: RU-4250
    Regular Price $94.99

    In Stock

    Not sure it fits your vehicle?
    Email sales@berryperformancesales.com with your year, make, model and engine, and we'll help you check fitment before you order.
    Fast Fulfillment: In-stock orders typically ship within 1 to 2 business days.
    Free Shipping on Orders Over $99 | Excludes freight shipments
    International Shipping Available: email sales@berryperformancesales.com for a quote.
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    The K&N RU-4250 is a universal clamp-on air filter with a round tapered, conical shape. It uses K&N reusable cotton filter media and clamps onto any air inlet that matches its 3.75 inch flange diameter, making it a common choice for custom and replacement intake setups where high airflow is wanted.

    Specifications:

    • Type: High-Flow Air Filter Element
    • Style: Clamp-On, Round Tapered (Conical)
    • Base Diameter: 5.375 in
    • Top Diameter: 4.375 in
    • Height: 5 in
    • Flange (Inlet) Diameter: 3.75 in
    • Filter Media: Reusable Cotton
    • Color: Red
    • Fitment: Universal
    • Quantity: Each
    • Part Number: RU-4250

    FAQ

    What size inlet does the K&N RU-4250 fit?

    The RU-4250 has a 3.75 inch flange diameter, so it clamps onto any intake tube or adapter with a 3.75 inch outside diameter.

    Is the K&N RU-4250 washable and reusable?

    Yes. It uses K&N reusable cotton filter media that can be cleaned and re-oiled instead of being thrown away and replaced.

    What are the dimensions of the RU-4250?

    It measures 5.375 inches across the base, tapers to 4.375 inches at the top, and stands 5 inches tall, with a 3.75 inch mounting flange.

    Is the RU-4250 vehicle-specific?

    No. It is a universal clamp-on filter and is not vehicle-specific. It fits any application with a matching 3.75 inch flange diameter.

    Shipping Policy
    • Free shipping on orders over $99 (excludes freight shipments).
    • In-stock orders typically ship within 1 to 2 business days. Weekend and holiday orders are processed the next business day.
    • Orders ship from Defiance, Ohio and a nationwide network of warehouses and manufacturers.
    • Items showing an ETA are not in stock yet. ETAs come from the manufacturer and can change.
    • No P.O. Boxes. International orders need a shipping quote, so email us first.

    Read the full Shipping Policy

    Return Policy
    • 30-day return window from the ship date. Returns must be approved first; email sales@berryperformancesales.com with your order number.
    • Items must be unused, complete and in the original packaging.
    • A 20% restocking fee applies, and return shipping is paid by the buyer.
    • Not returnable: installed or modified parts, opened or used programmers and tuners, custom orders, Open Box, and Clearance or Final Sale items.
    • Damaged, defective or incorrect items must be reported within 48 hours of delivery with photos.

    Read the full Return Policy

    Disclaimer

    All products are sold for off-road use only unless otherwise specified. Buyer assumes all responsibility for installation and operation. Seller is not liable for any incidental, indirect, or consequential damages — including engine failure, labor costs, or vehicle downtime — resulting from the use of any product sold.

    By making a purchase from Berry Performance Sales, you acknowledge and agree to abide by the terms and conditions of these Policies.

    For any questions or concerns, please contact us — we’re always happy to help.

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