"Rolling coal and crushing souls." Boss Ross Diesel: unapologetically overboosted.

More boost, less excuses.

We don't chase horsepower, we drag it -- screaming out of your mill.

Built for torque, tuned for trouble.

From farm trucks to track monsters—we make 'em all spool happy.

Lift it, lock it, launch it—regret nothing.

Built to crawl over rocks, mall curbs optional.

Turning daily drivers into trail survivors—one questionable mod at a time.

We put the ‘overkill’ in overland. Boss HP —where mild upgrades go to die.

If it ain’t broke, you’re not pushing hard enough.

Built to tow your house, and scare your neighbors.

Making smoke signals since… well, since your last tune.

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*Discontinued**Discontinued*~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in H

Name: ***Discontinued******Discontinued***~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in H
Brand: K&N Engineering
SKU: KANRX-3990-1
Price: 139.99 USD
Availability: InStock

*Discontinued**Discontinued*~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in H

$139.99 USD

~~$139.99 USD~~ $139.99 USD

Sale Sold out

***Discontinued******Discontinued***~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in H

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Product	Product subtotal	Quantity	Price	Product subtotal
*Discontinued**Discontinued*~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in HKANRX-3990-1	*Discontinued**Discontinued*~(1.4 lbs. 11X6X6)~ 3in FLG. 6in B. 4in T. 8-11/16in HKANRX-3990-1 Regular price ~~$139.99~~ Sale price $139.99/ea	$0.00	Quantity	Regular price ~~$139.99~~ Sale price $139.99/ea	$0.00