Neighbor Haters Slip-On Exhaust. The new Neighbor Haters by Cobra are not for the faint of heart. These are an aggressive slip-on muffler, for those who think loud just isn't good enough. For riders who think that too loud is just about right. Sold as a set. Limited lifetime warranty. Made in the U.S.A. Note: NOT legal for sale or use in California on and pollution-controlled motor vehicles. Detailed Specifications: The constant velocity cores are designed specifically for the Milwaukee Eight engine platform, to provide the best sound and performance. The 3" muffler body morphs to 3.25" at the rear, and instead of using a billet aluminum tip there is a rolled steel tip and separate inner flared tip.