GTHAUS MEISTERSCHAFT BMW / M3 E90/E92/E93 Section 2 Bolt-on SR Connecting Pipes upgradeSection 2 connects the mid section piping to the resonator which prevents cutting the M3 piping to create a full bolt on system. GTHAUS systems do come with the Section 2 Pipes in Stainless Steel (SUS). Upgrade to Titanium to save additional weight Why GTHAUS? Sound, performance, and build quality. Since the beginning, we at GTHAUS have strived to set our brand above the rest, weve done so by combining these key components: Sound, Performance, Build