K&N parts matching Champ Labs. AF3974 air filter

The Champ Labs. AF3974 air filter cross references with the K&N air filter parts below. K&N offers compatible air filters for many Champ Labs. air filters giving you an alternative.
ProductPart NumberProduct Image 
K&N Replacement Air Filter
  • Designed to Increase Power
  • Million Mile Limited Warranty
Rob Van Arsdale, Fremont, California
I immediately noticed the increased performance. It was like driving a different car.
Mark Beeksma, Whitby, Canada
Always a fan of K&N air filters. Definitely adds boost to acceleration. I had a 2002 Mazda Protege that I had to scrap, but one of the things I took out of it was the 8 year old K&N air filter that I maintained. It was still in great shape. I gave it to another Protege owner.
SHEK, BVT
WOWOWOWOWOWO!!!!!!!!!!!!!!! what a change..<br /> I already feel the power and increase in gas mailage .....quick ..... Awesome air filter..<br /> I dont know why I didnt hear about this(K&N)product before<br /> <br /> This is not only a air filter, its a bullet.. fast, power and sound!
33-2293 K&N 33-2293 Replacement Air Filter
List Price: $75.79
Your Price: $48.99
K&N Replacement Air Filter
  • Designed to Increase Power
  • Million Mile Limited Warranty
William Smith, Kingsport, Tennessee
Easy to install, fits perfectly. Fair price. Looking forward to years of good service.
Michael Scott, Monkland, Australia
Thank you for a very fast delivery and an excellent product.
Donald Grim, Texas
This filter made a dramatic difference in my performance of my MX 5 2013 hardtop convertible. Thanks.
33-2335 K&N 33-2335 Replacement Air Filter
List Price: $76.69
Your Price: $48.99
K&N Replacement Air Filter
  • Designed to Increase Power
  • Million Mile Limited Warranty
Clive Williams, Leics, United Kingdom
I have been using K&N filters exclusively for 35 years and would use no other - I still have the my first K&Ns, which are destined for reuse. All our vehicles get a K&N at their first service. The current purchase was for a Mazda 3 I-Stop that appears to be a limited run design. Annoyingly, it is more expensive than the standard larger K&N for this vehicle. Purchase from K&N UK direct was as cheap as anywhere else with a delivery that was swift and trouble free. The replacement and fit were perfect as usual.
Marek Kozolka, Bratislava, Slovakia
Mazda 2.0l 111kw 2011, the best buy for the car.. Ready for new exhaust system..:)
Tim Sides, Coedpoeth, United Kingdom
Okay, so first I have to thank the guy who said it fits the i-Stop Mazda 3, because I wasn't sure until I read that. Secondly, the air filter I took off was filthy, had grass in and everything, so basing my experience after that. Can I tell the difference? I think I can, but that might be wishful thinking, the car does feel more responsive, and whereas it had a tendency to stall starting off in cold damp weather, now it seems to be flawless. But I have only done about 100 miles since buying the filter. Am I happy with my purchase? Yes. Would I buy from again? No doubt.
33-2999 K&N 33-2999 Replacement Air Filter
List Price: $83.49
Your Price: $53.99