K&N Round Air Filter Assembly 5.25in ID / 5in Height / 5.125in Neck Flange / 1 1/4in Drop Base

K&N Round Air Filter Assembly 5.25in ID / 5in Height / 5.125in Neck Flange / 1 1/4in Drop Base

Marsoni

M251S

$157.99

Get it in 3 business days with 1 day shipping. Friday, May 29

K&N Round Air Filter Assembly 5.25in ID / 5in Height / 5.125in Neck Flange / 1 1/4in Drop BaseK&N's custom air cleaner assemblies are designed with the racer in mind. They incorporate good looks as well as the superior air flow that you expect from K&N. These custom air cleaner assemblies are designed for use with any engine that uses a round element air cleaner housing. They incorporate our famous K&N Air Filters and provide more air flow than other assemblies of this type. Available in 4 different designs, the perfect assembly is sure to be

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Exchange/Return Notes

We offer a 30-day return/exchange service after receiving.
Final sale items are not eligible for returns or exchanges.
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I have a 2017 vengeance and it has had a bit of sun even though it stays in a building when not used. It was getting a bit of fading even though I polish it each year. I wanted to try something and this was what I settled one after looking. Yes it is a bit of work on a 43’ fifth wheel. I ordered 2 kits but after a week of working on it after work we went camping and where next to a week old fifth wheel and he asked what I used to make it look better than his. It has a mirror finish on it now. After 6 months it still looks great and it’s durable and ease of use. What an effective product

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Reviewed in the United States on September 23, 2024

Verified Purchase

Linda Carol Allen

Carnegie, US

★★★★★ 5

Great product for rv

This is an excellent product. The front of our camper was very faded from the sun even though we keep it under a cover. After four coats, it looks like a different RV. We are going to do the entire camper. The difference is amazing. You will be so happy with the results. We would give it a 10 if possible.

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Reviewed in the United States on October 19, 2025

Verified Purchase

Royal foil

Louisville, US

★★★★★ 5

Amazing fiberglass restoration.

So easy to use and fabulous results. A few years back I had tried Maguires products to restore the shine on a 5th wheel. That was so labor intensive and the results were struggled to achieve faded quickly. I hesitated to Poli Glow due to the cost and our prior attempts lackluster results. I was able to get the restoration kit at a discount on Black Friday through the stores website and tackled the camper with the temps between 60-90 as instructed. I bought 2 of those kits just to find out that due to the climate and UV exposure the number of coats I would need for the Poli Glow was going to exceed the amount I had on hand through the 2 restoration kits. So I had to scramble to buy another bottle of Poli Glow. Applying this product is just time consuming and not difficult. Make sure to properly prepare the surface before using poliglow. The whole system turn a badly oxidized camper into a shiny finish. I am truly shocked. Hopeful the results will last a while. 5th wheel camper 40 foot long. I have used 3 poliglow bottles (12 coats), 1 bottle poli ox, 1.5 bottles of Poli wash (of course, not in that order). I potentially need 1 more bottle of Poli Glow to finish nose cone/basement area (basement area is still in good condition so may not do this area if I can get the nose cone with the remainder of the Poli glow I have.)

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Reviewed in the United States on January 19, 2026

Verified Purchase

Kindle Customer

San Leandro, US

★★★★★ 4

Worth the time and effort.

After proper surface prep and 6 applications, my badly sun damaged RV shined like new, with many compliments. However, after a few months under the cover, the fiberglass surfaces that were in contact with the occasionally wet cover in the Florida sun discolored badly, and will have to be wet sanded and the coating re-applied. Also, the polish does not hold up well where boat fenders rub against the coating, and it wears away in cockpit areas that are heavy hand traffic, like hatchways and around handrails. Overall a decent product, I will probably re-apply in a couple seasons.

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Reviewed in the United States on September 23, 2025

Verified Purchase

Randy Brown

Louisville, US

★★★★★ 5

Brings old paint back to life.

Best product for fiberglass oxidation. Tried many different wax’s and compounds. Poly Glow did what the wax could not do.

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Reviewed in the United States on April 29, 2026