NIB-2 they list for 69.99 ea. By Dynatech,vortex insert cones Stainless steel inserts install near the exit of the collector or muffler outlet to provide a large friction area to reflect and dissipate sound.No significant backpressure has been introduced,so the engine is still able to use the scavenge ability to create horsepower and torque. SELL $100.oo ,thats over a $40 saving!
