Bosch LSU 4.9 5-wire, wide-band O2 sensor.
Compatible with the LM-2, LC-2, and MTX-L, SCG-1, DLG-1, PSB-1, and PSN-1.

NOTE:
 
The latest generation widebands are compatible with both the Bosch LSU 4.2 and 4.9.
Please note that the sensor connector is different for each sensor.
Reference the Sensor/ Sensor cable identifier image