With internal disc. Comes with 1 3/4" head pipes covered with 2.25" heat shields for the Fat Look without compromising performance. Mufflers are 3.5" diameter and flare out to a 4" Slash Cut end. Overall length is 16", making it a short aggressive large volume muffler. With the 12, included, 4" diffuser discs per muffler SuperTrapp measured a 15% HP and 12% torque gain on the dyno.

Harley Davidson Softail 1984-2011

Note: Includes 18mm O2 plugs for 86-06 Softail, used only when O2 sensors are not present on the motorcycle