Connector 1: For GM 12Pins OBD1 Male Connector. 1 x 12 Pin OBD1 To 16 Pin OBD2 Convertor Adapter Cable For GM Diagnostic Scanner US. It is used for GM vehicles and its For GM 12 pins allows you to connect a GM vehicle with a 12 pins socket with your existing OBD2 16 pins tool.
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