Unlock the true potential of your BMW M3 F80 or BMW M4 F82 with the Untd. Performance 3″ Catless Downpipe. Designed specifically for the S55 3.0L Twin-Turbo Inline-6 engine, this downpipe removes the restrictive factory catalytic converters, allowing for maximum exhaust flow, quicker turbo spool, and significant performance gains. Whether you’re aiming for higher power levels, faster throttle response, or an aggressive exhaust sound, this catless downpipe is built to deliver the ultimate performance experience.