Bassani Longtube Headers Bassani 2007+ Mustang Shelby GT500 Stainless Longtube Headers. Stainless Longtubes, 1 3/4″ > 1 7/8″, 16g primary tubes, 3/8″ thick laser-cut flange, with 3″ collector Bolts directly up to Bassani Part# 5407R2 or Part# 5407R3 and Part #5407R5 Unsurpassed quality and fit, superior materials and expert craftsmanship. Mandrel bent 14 ga. Carbon steel primary tubes for durability. Exclusive Extractor Collector: induces a scavenging effect and further improves performance. S.S. Comp TM Stainless Header Gaskets cure header leaks. Ball and socket exit connectors for a gasket-free connection to your Y-pipe or X-pipe crossover section Bassani Headers include all nuts, bolts, gaskets, hardware and detailed instructions for a perfect fit. With over three decades of design experience and maximum performance, Bassani has learned what works and what doesn’t. Bassani has the ability to develop product designs to optimize performance, and the technical expertise to implement these.