Set of 4 extensions for relocating O2 sensors when installing long tube headers on the LS2 or LS3. The relocation extensions are made from the correct TXL OEM wire, utilizing factory style connectors. The extensions are not included when purchasing your long tube headers. These units are exact fit for your C6 Corvette and not generic extensions. Due to location of the O2 sensor, they could be used with Kooks or any long tubeheader manufacture.