Did a stage one upgrade except for a tuner.That will come next. I have a 2012 ST Deluxe & there is a cat. In these pipes some where? I shined my flash light into the header pipes & saw nothing but a hollow pipe all the way back th the bend. My slip on's are hollow as well except for the 2.5 baffle @ the tip(RUSH slip on's). The stock muffs pictured have rolled wire & a plug in the muff tip.Could this be the catalytic converter? Have read that a converter is massive amounts of cotton like stuffing put into a pipe to clean the atmosphere & make the world a safer place. Here is a couple of pics for the above post.