Don't Hayman-Rees manufacture the genuine ones ? Look for a Hayman-Rees outlet near you. Also, a good towbar fitter will be able to hide the wire harness inside the boot for you, rather than have an ugly plug below the bumper, they usually hide them in the tyre well, then when you need it, the flat wire harness suitable for this (Looks like a PC SCSI cable) simply fits through the boot seal and it hangs out of your boot to the trailer plug. When finished - tuck it back in. Factory wont do this. I'd love to see a Stivo try tow a boat to begin with :P Then hitting lift with the strain of towing the additional weight will destroy the engine in a hurry.