Easy to install. Affordable. Reliable.   G4X PlugIn ECUs offer the latest in engine management technology, designed to easily maximize the potential from your car.   This ECU fits inside the factory OEM enclosure. Installation is a breeze, with no alteration of the factory wiring loom required for the models listed below.  Designed for the WRX V7-9 EJ20 (GD/GG chassis, MY2000-2007 with cam control, 2.0L models only). Please check your connector matches the header in the listed photo before purchasing. This ECU fits 5 Plug ECUs.  This ECU works for manual transmissions only.   Air temp sensor highly recommended.  Most factory features are supported.  Check the features tab for I/O expansion options. Download manual here Download full G4X specifications here.