Wiper motor nut. A solid metal or plastic block with a threaded hole in the center which is used to tighten or adjust the HVAC Case. Back Glass Wiper Motor Nut. Bumper Cover Support Rail Nut. Instrument Panel Air Duct Nut. and Washer -. Back Glass Wiper Motor. Bumper Cover Support Rail. HVAC Unit Case. Instrument Panel Air Duct. Intake Duct. Mount frame. Striker. Under Cover.