Oxygen sensor O2 connector for Terminator X The Holley 558-463 converts and connects the main harness of the Holley EFI system to be compatible with the Terminator X Wideband O2 sensor, part number ( Phone number appears when clicking the contact button ) . This converter is specific to the Holley Terminator X EFI system and will not work with LSU 4.2 O2 sensors.