A completely new downstream oxygen sensor.
An NGK OEM sensor NTK 24821 - fits:
Saab:
- 9-2X: 2006
Subaru:
- Forester: 2004 - 2010
- Impreza: 2004 - 2014
- Legacy: 2005 - 2007
- Outback: 2005 - 2007
- WRX STI: 2013 - 2014
Got a wrong one from the store (needed an upstream). The sensor is unpacked but was never used. Originally bought for $190.