BMW list this as an option for the electric tow bar
But as mentioned above, I also have the Thule roof bars and cycle carriers. Although the boot rack would be useful for when the kayak is on the roof when we go camping.
2004 BMW E85 Z4 3.0 SE with full Sport pack
2012 BMW F30 320d Sport Saloon with Sports Automatic Transmission, M-Sport Adaptive Suspension, Visibility and Professional Media