Used on 1968-71 Corvettes only, this is the wire that goes from the dash harness ignition switch connector, through the firewall, to the T.I.
Transistorized ignition is a very specialized performance option that works well, when it works. When it doesn't, it can be very frustrating. From an originality standpoint, if your car was originally equipped with T.I., you would want to retain the T.I. system. If you are thinking of converting your car from OEM standard (non-electronic) ignition to T.I., don't do it!
Electrical components such as wires are non-returnable parts.
Always refer to a factory service manual when diagnosing engine service problems. You can damage electrical components if the proper procedures are not followed. Be sure you are replacing the correct part.