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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Your K&N Round Air Filter Assembly 5.25in ID / 5in Height / 5.125in Neck Flange / 1 1/4in Drop Base orders ship within 1-2 business days.

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Fast: 2-3 business days
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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 was dealing with night sweats almost every night. Waking up overheated, flipping my pillow over constantly, just uncomfortable and restless. It was starting to mess with my sleep in a real way. Since switching to this cooling pillowcase (and pairing it with a cooling blanket), it’s been a completely different experience. I’m actually staying cool through the night and not waking up soaked or irritated. The fabric feels cool to the touch right away and doesn’t trap heat like a regular pillowcase. It’s smooth, comfortable, and still feels good after washing. Not stiff or weird like some “cooling” materials can be. Is it magic? No. But does it noticeably reduce overheating and help you sleep better? Absolutely. If you run hot at night or deal with night sweats, this is one of those small upgrades that makes a big difference. I wish I had bought it sooner.

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Reviewed in the United States on March 19, 2026

Verified Purchase

Amazing Sally

Whiting, US

★★★★★ 5

so far so good

I was surprised at this pair of pillow cases only because the material seemed impossible to be cooling - it's that weird polyester blend. So far I have not awoken feeling sweaty around my face and scalp. I don't recall what I originally paid but I think it is great value for money! If you are sensitive to out of the box smell, I washed mine first and it didn't impede on the efficacy of the cooling!

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Reviewed in the United States on April 28, 2026

Verified Purchase

Devin Hill

Boise, US

★★★★★ 5

It’s like sleeping on a beach in San Vito lo Capo

Italian voice: I’m a big meaty fella so I put off a lot of heat ya hear. These pillow cases have changed my life. One moment they’re hot and the next you flip them and you’re blasted with a blast of ice cool what it feels like to chew 5 gum feeling capeesh. I would reccomend these pillow cases to even my grandma. If ya wanta get a rest so good that it feels like ya been sleeping with the fishes get these pillow cases, they’re the real deal. Then stop at Pauline’s joint and grab a slice of pizza say Vinnie sent ya. Anyways I gotta go my wife’s cooking up a mean lasgna and we’re gonna watch the dodgers. Let me know how these treat ya I guarantee they will change your life. Vinnie out

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Reviewed in the United States on February 15, 2026

Verified Purchase

Amazon Customer

Chelsea, US

★★★★★ 4

Soft "cooling" case.

Yes it is very cool when you lay on it. It doesn't stay cold though. Within a minute or 2 to whatever your temp is.

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Reviewed in the United States on December 25, 2025

Verified Purchase

CountryGal

Carnegie, US

★★★★★ 5

Great for hair and skin. Great buy.

These pillow cases are great for my hair and skin. They look good, hold up well in the washer and dryer, and the price is great. They are cooling. Of course I wish they could be more cooling, but honestly I'm not sure that's even possible. Great pillow cases. Already bought more for other heads. Would buy again.

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Reviewed in the United States on March 11, 2026