Used plug and wiring pigtail for the brake light warning switch located on the drum or disc brake distribution block mounted to the driver side fender apron. This is a plug and section of wire for repairing the underhood harness.
Specific to 68 - early 70 Cougars and Mustangs.
The only difference between the late and early pigtail is that the early plug is black and the late plug is white. No difference in wiring.