Bumper bracket nut. Left.STYLESIDE. Rear. Right.STYLESIDE. A solid metal or plastic block with a threaded hole in the center which is used to tighten or adjust the Differential Housing Mount. A solid metal or plastic block with a threaded hole in the center which is used to tighten or adjust the Differential Housing. Bumper Face Bar Mount Nut. Bumper Face Bar Nut. Bumper Face Bar Reinforcement Beam Nut. Hex. Flanged. Bracket retainer. Differential carrier. Differential Housing. Face Bar Reinforcement Beam. Inner Bracket U -. Insulator. Mount arm. Step.