This is a performance connect header system, designed for use with Stainless Works catbacks FTLTNCB4 or FTLTNCB4LMF. Header Features: • Primary Size: 1-¾” • Merge Collector for better scavenging • O2 bungs for tuning • 3” Collector • 304 Stainless Steel • Lifetime Warranty • TIG Welded American Made • ⅜” Thick Flanges • Performance Connect for full 3” connectionLearn More