Mufflers Nh R Black Fl 17-Neighbor Hater Slip On MufflersCobra's Neighbor Hater mufflers are not for the faint of heart These are an aggressive slip on muffler, for those who think loud just isn't good enough Start as round 4" tubes, then bell out to 4. 5", for an aggressive and classic design at the rear Internally, these mufflers have a perforated core with strategically spaced holes; This is done in order to produce an aggressive bark At the end of the baffle is a trumpet