This is the coolant Temp Sender for the dash temp gauge in Subaru motors. Ref ID: 21203AA030

Coolant temperature sensor This sensor lives in the thermostat housing and sends a signal to the gauge in the instrument cluster.  If your temp gauge is acting strangely or reading incorrectly,...

Subaru Oxygen Sensor (Denso 234-9015). OE number 22641AA280. Fits 03-06 Subaru 2.5L engines. Forester. Baja. 2.5L, 2003-04. 2.5L, front, all. Air-Fuel Ratio Sensor. 2.5L, 2003, air, fuel ratio. 2.5L,...