4.1 RCT Slip-On MufflerThe Factory 4.1 RCT incorporates FMF Resonance Chamber Technology™ both internally and externallyIn addition, achieves a shorter overall length that is less susceptible to crash damage and complementary to Factory Forward Engineering - moving the muffler closer to the motor to centralize massThe Factory 4.1 RCT is constructed from only aerospace grade materials that meet exacting specifications and is manufactured 100% at the Southern California factorySpark arrestor and quiet insert (94dB) included