This is a Bosch LSU 4.9 industry-standard heated 5-wire EGO sensor. These wideband air fuel ratio sensors are the very latest from Bosch and are used in many top quality tuning devices and also by professional dyno-tuners. Suitabe replacement sensor for the Prosport USA wideband kits.

Bosch 850cc injectors set (6) high impedence
Downpipe RAGE - Subaru WRX 1994-2000 3"
Banjo fitting M16x1.5 to -6AN
Turbosmart Kompact Plumb-Back BOV - Subaru Mazda
Tial 44mm wastegate (silver top)
Denso Kinugawa 600cc injector set (4) GDA GDB 