Factory Connect Off-Road: 2007-13 Chevy Silverado / GMC Sierra Truck Headers from Stainless Works – Increase performance and improve sound with our 1500 truck headers. These headers are designed to fit the factory connection point behind the factory catalytic converter. System includes Y-pipe and features 1-7/8″ diameter primary tubes and 3″ diameter lead pipes. Made from 304 stainless steel and TIG welded, these headers are constructed with 3/8″ thick flanges and come with 3″ diameter slip fit collectors with merge spikes. Designed to fit Chevy 1500 2WD/4WD 5.3L Double Cab with Standard Box or Crew Cab with either Short Box or Standard Box. Stainless Works headers are backed by a limited lifetime guarantee on material and workmanship and are made in the USA.