The factory is responsible for manufacturing the resulting product. All Viper branch manifolds and bolt-on systems are mandrel-bent (i.e. the pipe area remains constant throughout the bend). In terms of exhaust tuning, this is a primary requirement to achieve the best possible flow. The best quality materials are used and Viper branch manifolds carry a 2-year warranty. Viper branches are made of SAE 1010 mild steel tubing or polished 304-grade stainless steel. All our BOLT-ON systems are manufactured in 441 brushed finish stainless steel.