Shop By Vehicle
Top Categories
All Categories

Top Categories

All Categories

Hi, ! (Not you?)
My Account
Track Order
K&N RX-3990-1

K&N Round Tapered X-Stream Clamp-On Air Filter


Estimated to ship directly from the manufacturer on 11/20/18

K&N Round Tapered X-Stream Clamp-On Air Filter $92.99
Out of stock
Round Tapered X-Stream Air Filter
  • Flange Inside Diameter: 3" (76 mm)
  • Flange Length: 0.938" (24 mm)
  • Flange Type: Centered
  • Height: 8.688" (221 mm)
  • Base Outside Diameter: 6" (152 mm)
  • Top Outside Diameter: 4" (102 mm)
  • K&N RX-3990-1 Details

    3'' (76 mm) Flange Diameter

    • Pleated filter built in top
    • Washable and reusable
    • Low restriction
    • Clamp-on design


    Flange Type
    Overall Length (in.)
    Top Style
    Filter Re-Oiling Amount
    1.5 oz (44 ml)
    Top Material/Finish
    Air Filter Large End Diameter
    6 in (152 mm)
    Flange Offset
    0 in (0 mm)
    Top Outside Diameter
    4 in (102 mm)
    Air Filter Bottom Measurement (in.)
    6.000 diameter
    Air Filter Style
    Air Filter Top Measurement (in.)
    4.000 diameter
    Inlet Flange Inside Diameter (in.)
    Sold individually
    Flange Angle (Deg)
    Package Contents
    1 Air Filter
    Package Quantity
    Air Filter Shape
    Round Tapered
    Product Style
    Round Tapered Universal Air Filter
    Weight (lbs.)
    1.4 lb (0.6 kg)
    Flange Inside Diameter
    3 in (76 mm)
    Base Outside Diameter
    6 in (152 mm)
    Footnote 1
    1/4-20 Jack Nut Into Top
    Flange Length
    0.938 in (24 mm)
    8.688 in (221 mm)
    Manufacturer's Part Number:

    K&N Tapered Universal Filters are the best quality and performance air filter option for your application. Whether you are building your own cold air induction kit or you have an application that is just a little different K&N has many of the sizes and styles to fit your performance needs. Sold individually, unless otherwise noted.


    • K&N quality and performance
    • Several Sizes and Styles to fit your needs
    • Clean and re-oil instead of replace

    Items You Need

    Some parts are not legal for use in California or other states with similar laws / regulations

    Motor Vehicles

    WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.


    WARNING: Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Some examples of these chemicals are: lead from lead-based paints, crystalline silica from bricks and cement and other masonry products, and arsenic and chromium from chemically treated lumber. Your risk from exposure to these chemicals varies, depending on how often you do this type of work. To reduce your exposure, work in a well-ventilated area and with approved safety equipment, such as dust masks that are specially designed to filter out microscopic particles.

    Electrical Cords

    WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.