FAST® XFI™ Main Harnesses feature clearly labeled wires and pre-terminated ends with Weather Pack connectors for a perfect fit to your application. Environmentally sealed Weather Pack connectors were originally designed to be able to withstand exposure to extreme temperatures, moisture, and harsh engine compartment fluids and chemicals. They are heavily used by OEM Automobile/Truck, Construction, Off-Road, and Farm Equipment manufactures due to their high quality and excellent fitment.