01-05 HONDA GL1800: Rush Performance Dual Slip-On Exhaust (Chrome / 2.5" / 4") For performance, quality and sound, there is nothing else like a Rush Performance Slip-On Muffler.These mufflers have been engineered through thousands of hours of development, real world application and independently dyno tested in order to guarantee you To maximize performance of baffles, tuning modifications may be required.Note: May NOT be legal for use on public roads in the state of California.