(170mm Shell, 75mm Piping, 120mm Tip) The universal HKS Carbon-Ti muffler assemblies are the same high-quality units used in the HKS bolt-on exhaust systems. The 170mm Carbon-Ti muffler shell design is available in 75mm piping diameter for use with custom exhaust applications. Each assembly comes with a polished stainless mounting bracket for separate hangers to be welded onto.