The O2 sensor wire harness extension is designed for 2006-2014 Civic Sis. These extensions are great for installing an aftermarket header where the oem O2 sensor wires arent long enough to reach the new bung location. Designed for the Skunk2 header and exhaust.
Alpha Series Race O2 Sensor Extension; Plug And Play; For Use w/Skunk2 Headers And Exhaust;
For 06-11 Civic Si-For use with an aftermarket race header in which it is necessary to extend the Primary Oxygen sensor

Fitment:
Honda Civic Si 2006
Honda Civic Si 2007
Honda Civic Si 2008
Honda Civic Si 2009
Honda Civic Si 2010
Honda Civic Si 2011