Bumper cuts are cut on the underside of the bumper.
None visible : the cut will not be visible unless you look up at the bumper from the ground.
Visible: the cut will be visible when standing behind the vehicle.
No cut: No cutting required.
Many modern vehicles require a bypass relay for the towbar electrics to work correctly.
If your vehicle requires this relay then damage can occur to the cars electrics if one isn't fitted.
Our data is collected from the tow bar and tow bar wiring manufacturers with regards to whether your vehicle needs a bypass relay.
BMW 1 Series Coupe E82 2007-2014 Westfalia Detachable Towbar
E82 135i is not homologated for towing.
Vertical detachable tow bar demonstration video