New OEM Nissan Upstream (Front) Oxygen Sensor for all '05+ Nissan 350Z's and Infiniti G35's / FX35's equipped with the VQ35DE Engine.

'03 - '04 Front oxygen sensors can be found HERE.

Installed before the catalytic converters on the exhaust manifold, these sensors often prove to be extremely difficult to remove without destroying the threads when installing an aftermarket set of headers or forced induction setup.  These sensors are also referred to as an "Air-Fuel Ratio Sensor" by Nissan.

Sold individually, one sensor will fit either the Left or Right side of the vehicle.

Z1 Motorsports recommends the usage of an anti-seize compound on the threads of the oxygen sensor to make future servicing much easier.