The towbar you have selected is a Hayman Reese Step Lamp Protector (SLP) with Smartcode wiring.
Combine the Class 4 Hitch Receiver with a step and lamp protector and you have a very handy addition to any commercial vehicle. Whether you need to reach up onto the roof or climb inside the tub, the SLP is a favourite. The TBM can be removed when not in use.
Increasing technological and safety systems on vehicles are now enabling changes to occur when a vehicle is towing. Reverse park assist, blind-spot detection plus various trailer sway mitigation systems are prime examples of vehicle functions that can change if the vehicle is towing. Ensuring that these systems are correctly engaged involves more than simply the wiring and trailer ECU. Vehicles need to be programmed (coded) to allow the towbar harness and trailer ECU to be recognised and integrated into the body control system.