Quite a few original late production 1965 and Carryover 1966 GT350s have a plastic protective wrapping on each side of the metal rear brake line.
Apparently this was added by Shelby American to protect the metal lines where the lines could possibly rub against the rear traction bar brackets.
There was approximately a 7 ½” piece of this wrapping on each side.
This kit includes enough for each side to do one car.