$39.99 USD
MSRP $61.89 35.4% Off
Free Ground Shipping!
In Stock & Ready to Ship!
Find a Dealer

K&N E-4521 Air Filter

Replacement Filters > Replacement Industrial Air Filter
Rating Star 1 Rating Star 2 Rating Star 3 Rating Star 4 Rating Star 5   4.7 out of 5 stars   7 Customer Reviews
  • Washable and reusable
  • Ease of maintenance
  • High air flow with excellent filtration
  • Increased performance
  • Grease provided for secure fit
  • Lifetime limited warranty
The K&N E-4521 Air Filter fits some John Deere , John Deere 200, John Deere 210, John Deere 212, John Deere 214, John Deere 216, John Deere 300, John Deere 312, John Deere 314, John Deere 316, John Deere 400, John Deere 800 Aercore Aerator, John Deere F620 ZTrak, John Deere F680 ZTrak, John Deere F687 ZTrak, John Deere M653 ZTrak, Kohler CH18, Kohler CH19, Kohler CH20, Kohler CH21, Kohler CH22, Kohler CH23, Kohler CH24, Kohler CH25, Kohler CV16, Kohler CV17, Kohler CV18, Kohler CV19, Kohler CV20, Kohler CV21, Kohler CV22, Kohler CV23, Kohler CV25, Kohler K241, Kohler K301, Kohler K321, Kohler K341, Kohler K361, Kohler K532, Kohler K582, Toro 66 In Rake-O-Vac, Toro Multi Pro 1100, Toro Multi Pro 1200, Toro Multi Pro 1250, Toro Turf Sweeper 4800, Toro Workman 3100, and Toro Workman 3120 models. See vehicle applications link for details.
The K&N E-4521 replacement air filter is constructed using an oil-free synthetic media. A tube of sealing grease is provided to help ensure an airtight seal. The E-4521 provides superior filtration, protecting your equipment's engine. This K&N air filter can be cleaned and used again. The E-4521 air filter fits some Kohler, Toro Multi Pro and John Deere equipment, in addition to other applications.

[More Information on Small Engine & Light Industrial Air Filters]

Product Specifications

Filter MaterialNon-woven Synthetic
Height2.5 in (64 mm)
Inner WireNo
Inside Diameter5.5 in (140 mm)
Outside Diameter7 in (178 mm)
Top StyleOpen
Top MaterialNone
Air Filter ShapeRound
Package Contents1 Air Filter, 1 K&N 1oz Sealing Grease
Package Quantity1
Product StyleRound Air Filter
Weight0.9 lb (0.4 kg)
Product Box Height7.75 in (197 mm)
Product Box Length7.75 in (197 mm)
Product Box Width4.13 in (105 mm)

K&N E-4521 Air Filter Product Reviews

Wednesday, October 12, 2016 - Part E-4521
Easy to install. Hopefully it will be more cost effective in the long run.

Don McCarl
Woodland Park, Colorado
Saturday, July 23, 2016 - Part E-4521

Kirk DeFord
Poulsbo, Washington
Wednesday, May 25, 2016 - Part E-4521
I used this filter as a special Air Cleaner replacement for a 1955 Ford Thunderbird that otherwise would normally have an Oil Bath air cleaner. There is a company that makes air filter cleaner replacements for the old Oil Bath cleaners and I upgraded the included air filter to a K&N Filter, and I am happy with the results. For anyone else that has a 1955 or 1956 Ford Thunderbird with the original Oil Bath cleaner, you can upgrade to an air filter cleaner assembly from (Brand Name) and then upgrade the air filter to a K&N. Hope this helps any fellow '55-'56 T-Bird owners.

San Diego, California
Wednesday, October 22, 2014 - Part E-4521
I recently purchased a K and N filter for my 1974 wheelhorse c120 with an old Koher k301 cast iron engine on it, that I use for mowing, snow plowing and snow blowing in the winter. I got sick of paying out the nose each and every year for the OEM Kohler filters. So I installed my new K and N before mowing this past time. OH MY GOD. LOW END LIKE CRAZY. Like it never had before. Seems like once the governor kicks in it just PULLS through. Keeps the Rpms higher underload and overall it is just amazing that an air filter can do this to performance. Will I buy other K and N products absolutly. I am a small engine tech here in PA, I believe in keeping this older equipment running as long as possible and then some. I have a 3 other wheelhorses ranging in dates from the late 70-s to late 80s and a massy ferguson garden tractor that will definitely be getting a k and N  when the time comes. Another thing I noticed is it does not get near as dirty as my old oem filters with the old foam pre cleaners on them. Awsome product , and its awsome that you guys made it for such an old tractor like mine. Everyone wants the new cheapie stuff they sell at lowes and home depot, NOPE not me I like the good old garden tractors with so much torque they could climb a wall. I will defenetly be installing your filters on all my overhauls from now on no questions asked. Why throw money away in todays day and age?

Cody Frey
Boyertown, Pennsylvania
Sunday, June 22, 2014 - Part E-4521
Filter was easy to look up and determine which model to get. Item was packed well and shipped quickly. It fit my mower ok as expected. Have not been able to run it yet (while solving another fuel problem) to see if there is any noticeable performance difference.

Josef Stanek
Monday, November 18, 2013 - Part E-4521
Saves me lots of money on filters but would have been better with a foam prefilter as its on my mower and gets clogged by grass daily.

Wednesday, November 6, 2013 - Part E-4521
I have always had great results with your filters.

R Svedahl