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RK-3940 - K&N Drop-In High-Flow Air Filter

This part should fit your vehicle. It is a universal part.

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Part #: RK-3940
Notes: Universal Rubber Filter
MSRP: $295.99
Your Price: $186.43
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Air Filter Color Red
Air Filter Height 2.188 in (56 mm)
Air Filter Material Cotton Gauze
Air Filter Outlet Shape Not Flanged
Air Filter Shape Unique
CARB EO Number D-269-50
Clamp Material Stainless Steel
Clamp Style Regular
Clamps Included 2
Color Black
Estimated HorsePower Gain 7.14 HP @ 5313 RPM
Horse Power Increase 7 HP
Inlet Diameter 1.688 in (43 mm)
Mounting Hardware Included Yes
Neck Flange 1.688 in (43 mm)
Overall Height 2.75 in (70 mm)
Product Style Motorcycle Intake System
Replacement Filter E-3982
RPM 5313
Style Unique
Top Material/Finish Black Powder Coated
Top Style Metal
Weight 4.1 lb (1.8 kg)

All Fitments

Year Model SubModel Cylinders Liter Aspiration Eng Desg. Fuel Notes
0 - 0 NON APPLICATION SPECIFIC ALL ALL ALL ALL ALL ALL California Air Resources Board Exempt: No
0 - 0 NON APPLICATION SPECIFIC ALL ALL ALL ALL ALL ALL California Air Resources Board Exempt: Yes; CARB EO: D-269-50

Product Description

K&N Replacement High-Flow Air Filters are The Original High-Flow Air Filter.

Since 1969 K&N Engineering has been designing, manufacturing, and enhancing High-Flow Air Filters for the automotive and motorcycle enthusiast interested in maximizing horsepower and acceleration. Since K&Ns humble beginnings they have designed and manufactured over 2,400 High-Flow Air Filters to fit most modern passenger vehicles and over 500 High-Flow Air Intake Systems to fit vehicles driven by enthusiast minded drivers. K&N not only has more applications than any other manufacturer of similar product, K&N invented the High-Flow category and the High-Flow Technology that supports it. K&N also makes thousands of racing and specialty type air filters and is the only air filter used at the Indianapolis 500 Race.


  • High Air Flow with Excellent Filtration
  • Designed to Increase Horsepower and Acceleration
  • Washable and Reusable
  • Will NOT Void Vehicle Warranty
  • Lasts up to 50,000 miles before cleaning is required depending on driving conditions
  • K&N Million Mile Limited Warranty
  • Emissions Legal in all 50 US States.
  • Economical, a K&N Air Filter Will Last the Life of Your Automobile
  • Works with Original Equipment Manufacturer Vehicle Electronics
  • Easy High Performance Add-on
  • Environmentally Friendly

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