GM LS1 Oxygen O2 Sensor Extension Cable for Camaro Firebird 24" Set includes (1) 24" Cable Extension This is the Black Square 4-pin plug. It is different than the Gray Square 4-pin Uses the same GM Factory Delphi/Packard connectors, terminals and seals as the OEM wiring harness High Quality, Heat Resistant, Heavy Duty Construction Sold and shipped only by authorized OBD Innovations&#0174; dealers.