Service brakes, including trailer brake connections.
Parking (hand) brake.
Steering mechanism.
Lighting devices and reflectors.
Tires.
Horn.
Windshield wiper or wipers.
Rear-vision mirror or mirrors.
Coupling devices.
Wheels and rims.
Emergency equipment.
-Service brake components that are readily visible to a driver performing as thorough a visual inspection as possible without physically going under the vehicle, and trailer brake connections
-Lighting devices, lamps, markers, and conspicuity marking material
-Wheels, rims, lugs, tires
-Air line connections, hoses, and couplers
-King pin upper coupling device
-Rails or support frames
-Tie down bolsters
-Locking pins, clevises, clamps, or hooks
-Sliders or sliding frame lock
49 C.F.R. §392.7