Unlock the full auditory potential of your Harley-Davidson's engine with the Dr. Jekill & Mr. Hyde® 4.5" Big Shot Slip-On Mufflers. With electronic or manual adjustment, you’ll have complete control over the sound, switching between a quiet, refined tone and a powerful roar to match your mood and riding style. Dr. Jekill & Mr. Hyde has been the industry leader in adjustable exhaust systems for more than 25 years. These mufflers, which have been tried and tested by riders all over the world, offer the ideal mix of performance, sound, and versatility. These mufflers, which have been made in Holland since 1997, are designed for people who demand control. The future of sound is here. The power is in your hands.